STD::BASIC_ISTREAM(3)

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🌸 `std::basic_istream< _CharT, _Traits >(3)` 🌸 — Library Functions Manual

✨ NAME ✨

std::basic_istream< _CharT, _Traits > — bestie, it's the template class basic_istream. That's it. That's the whole vibe. 💖

🦋 SYNOPSIS 🦋

#include <istream>

Okay so first things first, this class inherits std::basic_ios< _CharT, _Traits >. Family tree moment. 🌳

And it's inherited by a whole friend group: std::basic_ifstream< char >, std::basic_ifstream< wchar_t >, std::basic_iostream< char >, std::basic_iostream< wchar_t >, std::basic_istringstream< char >, std::basic_istringstream< wchar_t >, std::basic_ifstream< _CharT, _Traits >, std::basic_iostream< _CharT, _Traits >, and std::basic_istringstream< _CharT, _Traits, _Alloc >. Iconic lineage fr fr. 👑

🎀 Classes

class sentry — does the setup work for input streams. Think of it as the little pre-game ritual before any extraction happens. It's giving backstage pass. 🎟️

🌈 Public Types

typedef ctype< _CharT > __ctype_type
typedef basic_ios< _CharT, _Traits > __ios_type
typedef basic_istream< _CharT, _Traits > __istream_type
typedef num_get< _CharT, istreambuf_iterator< _CharT, _Traits > > __num_get_type
typedef basic_streambuf< _CharT, _Traits > __streambuf_type
typedef _CharT char_type
enum event { erase_event, imbue_event, copyfmt_event } — the set of events that may be passed to an event callback. Yes queen, these are the events.
typedef void(* event_callback) (event __e, ios_base &__b, int __i) — the type of an event callback function. Basically the shape of the function you hand over. 💅
typedef _Ios_Fmtflags fmtflags — this is a bitmask type.
typedef _Traits::int_type int_type
typedef _Ios_Iostate iostate — this is a bitmask type too.
typedef _Traits::off_type off_type
typedef _Ios_Openmode openmode — also a bitmask type. They really said "bitmask" three times, and honestly? Slay.
typedef _Traits::pos_type pos_type
typedef _Ios_Seekdir seekdir — this one's an enumerated type, not a bitmask. Different energy.
typedef _Traits traits_type
typedef num_put< _CharT, ostreambuf_iterator< _CharT, _Traits > > __num_put_type

💜 Public Member Functions

Okay bestie, this is the big list, hydrate before you read it. 🍓

basic_istream (__streambuf_type *__sb) — base constructor. The origin story. 🌱
virtual ~basic_istream () — base destructor. It says goodbye. 😭
template<typename _ValueT> basic_istream< _CharT, _Traits > & _M_extract (_ValueT &__v)
const locale & _M_getloc () const — locale access.
void _M_setstate (iostate __state)
bool bad () const — fast error checking. Is it bad? Check fast.
void clear (iostate __state=goodbit) — [re]sets the error state.
basic_ios & copyfmt (const basic_ios &__rhs) — copies the fields of __rhs into this. Copy-paste but make it ✨format✨.
bool eof () const — fast error checking.
iostate exceptions () const — throwing exceptions on errors.
void exceptions (iostate __except) — throwing exceptions on errors.
bool fail () const — fast error checking.
char_type fill () const — retrieves the empty character. Not an empty personality, just an empty char. 🫶
char_type fill (char_type __ch) — sets a new empty character.
fmtflags flags () const — access to format flags.
fmtflags flags (fmtflags __fmtfl) — setting new format flags all at once. All at once, no cap.
streamsize gcount () const — character counting.
basic_istream< wchar_t > & getline (char_type *__s, streamsize __n, char_type __delim)
basic_istream< char > & getline (char_type *__s, streamsize __n, char_type __delim)
- These are explicit specialization declarations, defined in src/istream.cc. 📍
locale getloc () const — locale access.
bool good () const — fast error checking.
basic_istream< wchar_t > & ignore (streamsize __n)
basic_istream< char > & ignore (streamsize __n)
basic_istream< wchar_t > & ignore (streamsize __n, int_type __delim)
basic_istream< char > & ignore (streamsize __n, int_type __delim)
locale imbue (const locale &__loc) — moves to a new locale. Glow-up, but for locales. 🌍
long & iword (int __ix) — access to integer array.
char narrow (char_type __c, char __dfault) const — squeezes characters.
__istream_type & operator>> (__streambuf_type *__sb) — extracting into another streambuf.
__istream_type & operator>> (void *&__p) — basic arithmetic extractors.
streamsize precision () const — flags access.
streamsize precision (streamsize __prec) — changing flags.
void *& pword (int __ix) — access to void pointer array.
basic_streambuf< _CharT, _Traits > * rdbuf () const — accessing the underlying buffer.
basic_streambuf< _CharT, _Traits > * rdbuf (basic_streambuf< _CharT, _Traits > *__sb) — changing the underlying buffer.
iostate rdstate () const — returns the error state of the stream buffer.
void register_callback (event_callback __fn, int __index) — add the callback __fn with parameter __index.
fmtflags setf (fmtflags __fmtfl) — setting new format flags.
fmtflags setf (fmtflags __fmtfl, fmtflags __mask) — setting new format flags.
void setstate (iostate __state) — sets additional flags in the error state.
basic_ostream< _CharT, _Traits > * tie () const — fetches the current tied stream.
basic_ostream< _CharT, _Traits > * tie (basic_ostream< _CharT, _Traits > *__tiestr) — ties this stream to an output stream. Literally tying the knot. 💍
void unsetf (fmtflags __mask) — clearing format flags.
char_type widen (char __c) const — widens characters.
streamsize width () const — flags access.
streamsize width (streamsize __wide) — changing flags.
__istream_type & operator>> (__istream_type &(*__pf)(__istream_type &)) — interface for manipulators.
__istream_type & operator>> (__ios_type &(*__pf)(__ios_type &)) — interface for manipulators.
__istream_type & operator>> (ios_base &(*__pf)(ios_base &)) — interface for manipulators.

🔥 Extractors

So, all the operator>> functions (aka the formatted input functions) share some common behavior, and you need to know it:

Every single one starts by constructing a temporary object of type std::basic_istream::sentry with the second argument (noskipws) set to false. That has several effects, and it all wraps up with the setting of a status flag — see the sentry documentation for the full tea. ☕

If the sentry status is good, the function tries to extract whatever data is appropriate for the type of the argument.

⚠️ If an exception is thrown during extraction, ios_base::badbit will be turned on in the stream's error state (without causing an ios_base::failure to be thrown) and the original exception will be rethrown if badbit is set in the exceptions mask. Not me warning you dramatically, but like, do read that twice. 😭

__istream_type & operator>> (bool &__n) — integer arithmetic extractors.
__istream_type & operator>> (short &__n) — integer arithmetic extractors.
__istream_type & operator>> (unsigned short &__n) — integer arithmetic extractors.
__istream_type & operator>> (int &__n) — integer arithmetic extractors.
__istream_type & operator>> (unsigned int &__n) — integer arithmetic extractors.
__istream_type & operator>> (long &__n) — integer arithmetic extractors.
__istream_type & operator>> (unsigned long &__n) — integer arithmetic extractors.
__istream_type & operator>> (long long &__n) — integer arithmetic extractors.
__istream_type & operator>> (unsigned long long &__n) — integer arithmetic extractors.
__istream_type & operator>> (float &__f) — floating point arithmetic extractors.
__istream_type & operator>> (double &__f) — floating point arithmetic extractors.
__istream_type & operator>> (long double &__f) — floating point arithmetic extractors.

🌸 Unformatted Input Functions

Same deal, but different. All the unformatted input functions share some common behavior too:

Each starts by constructing a temporary object of type std::basic_istream::sentry with the second argument (noskipws) set to true. Several effects follow, concluding with the setting of a status flag — again, sentry documentation has the details. 🧚

If the sentry status is good, the function tries to extract whatever data is appropriate for the type of the argument.

The number of characters extracted is stored for later retrieval by gcount(). 📝

⚠️ If an exception is thrown during extraction, ios_base::badbit will be turned on in the stream's error state (without causing an ios_base::failure to be thrown) and the original exception will be rethrown if badbit is set in the exceptions mask. Same warning, same energy, still important.

int_type get () — simple extraction.
__istream_type & get (char_type &__c) — simple extraction.
__istream_type & get (char_type *__s, streamsize __n, char_type __delim) — simple multiple-character extraction.
__istream_type & get (char_type *__s, streamsize __n) — simple multiple-character extraction.
__istream_type & get (__streambuf_type &__sb, char_type __delim) — extraction into another streambuf.
__istream_type & get (__streambuf_type &__sb) — extraction into another streambuf.
__istream_type & getline (char_type *__s, streamsize __n, char_type __delim) — string extraction.
__istream_type & getline (char_type *__s, streamsize __n) — string extraction.
__istream_type & ignore (streamsize __n, int_type __delim) — discarding characters.
__istream_type & ignore (streamsize __n) — simple extraction.
__istream_type & ignore () — simple extraction.
__istream_type & ignore (streamsize __n, char __delim) — simple extraction.
int_type peek () — looking ahead in the stream. 👀 No touching, just looking.
__istream_type & read (char_type *__s, streamsize __n) — extraction without delimiters.
streamsize readsome (char_type *__s, streamsize __n) — extraction until the buffer is exhausted, but no more. Boundaries, we love to see them. ✋
__istream_type & putback (char_type __c) — unextracting a single character.
__istream_type & unget () — unextracting the previous character.
int sync () — synchronizing the stream buffer.
pos_type tellg () — getting the current read position.
__istream_type & seekg (pos_type) — changing the current read position.
__istream_type & seekg (off_type, ios_base::seekdir) — changing the current read position.
operator bool () const — the quick-and-easy status check.
bool operator! () const — the quick-and-easy status check.

👑 Static Public Member Functions

static bool sync_with_stdio (bool __sync=true) — interaction with the standard C I/O objects.
static int xalloc () throw () — access to unique indices.

✨ Static Public Attributes ✨

static const openmode __noreplace — that's it, that's the attribute, no lil description attached, she simply exists 💅
static const fmtflags adjustfield — a mask of left|right|internal. lowkey a lifesaver for the 2-arg form of setf.
static const openmode app — seek to the end before each write. every single one bestie, no skipping.
static const openmode ate — open and seek to the end immediately after opening. it's giving "already at the back of the line" energy.
static const iostate badbit — indicates a loss of integrity in an input or output sequence (like, say, an irrecoverable read error from a file). this is the 💀 flag.
static const fmtflags basefield — a mask of dec|oct|hex. perfect for the 2-arg form of setf.
static const seekdir beg — request a seek relative to the beginning of the stream. back to square one, fr.
static const openmode binary — perform input and output in binary mode (as opposed to text mode). > this is probably not what you think it is; see https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary. no cap, go read it.
static const fmtflags boolalpha — insert/extract bool in alphabetic rather than numeric format. words over numbers, iconic.
static const seekdir cur — request a seek relative to the current position within the sequence. right where you left it, bestie.
static const fmtflags dec — converts integer input or generates integer output in decimal base.
static const seekdir end — request a seek relative to the current end of the sequence.
static const iostate eofbit — indicates that an input operation reached the end of an input sequence. the end, periodt.
static const iostate failbit — indicates that an input operation failed to read the expected characters, or that an output operation failed to generate the desired characters. it tried, it flopped 🥲
static const fmtflags fixed — generate floating-point output in fixed-point notation.
static const fmtflags floatfield — a mask of scientific|fixed. yes, it's for the 2-arg form of setf. you know the drill by now.
static const iostate goodbit — indicates all is well 🫶 everything's fine, nothing to see here, she's thriving.
static const fmtflags hex — converts integer input or generates integer output in hexadecimal base.
static const openmode in — open for input. the default for ifstream and fstream.
static const fmtflags internal — adds fill characters at a designated internal point in certain generated output, or identical to right if no such point is designated.
static const fmtflags left — adds fill characters on the right (final positions) of certain generated output. (i.e., the thing you print is flush left.)
static const fmtflags oct — converts integer input or generates integer output in octal base.
static const openmode out — open for output. the default for ofstream and fstream.
static const fmtflags right — adds fill characters on the left (initial positions) of certain generated output. (i.e., the thing you print is flush right.)
static const fmtflags scientific — generates floating-point output in scientific notation. science slay 🔥
static const fmtflags showbase — generates a prefix indicating the numeric base of generated integer output.
static const fmtflags showpoint — generates a decimal-point character unconditionally in generated floating-point output. she said "you WILL see my point".
static const fmtflags showpos — generates a + sign in non-negative generated numeric output.
static const fmtflags skipws — skips leading white space before certain input operations.
static const openmode trunc — truncate an existing stream when opening. the default for ofstream. bye bye old contents 🥀
static const fmtflags unitbuf — flushes output after each output operation.
static const fmtflags uppercase — replaces certain lowercase letters with their uppercase equivalents in generated output. LOUDER 📢

🎀 Protected Types 🎀

enum { _S_local_word_size } — a lil anonymous enum, just vibing, just holding a size.

🦋 Protected Member Functions 🦋

basic_istream (basic_istream &&__rhs)
basic_istream (const basic_istream &)=delete — copy construction? deleted. not today bestie.
void _M_cache_locale (const locale &__loc)
void _M_call_callbacks (event __ev) throw ()
void _M_dispose_callbacks (void) throw ()
template<typename _ValueT> __istream_type & _M_extract (_ValueT &__v)
_Words & _M_grow_words (int __index, bool __iword)
void _M_init () throw ()
void _M_move (ios_base &) noexcept
void _M_swap (ios_base &__rhs) noexcept
void init (basic_streambuf< _CharT, _Traits > *__sb) — all setup is performed here. the whole get-ready-with-me moment, right here.
void move (basic_ios &&__rhs)
void move (basic_ios &__rhs)
basic_istream & operator= (basic_istream &&__rhs)
basic_istream & operator= (const basic_istream &)=delete — copy assignment also deleted. consistency queen 💅
void set_rdbuf (basic_streambuf< _CharT, _Traits > *__sb)
void swap (basic_ios &__rhs) noexcept
void swap (basic_istream &__rhs)

💜 Protected Attributes 💜

_Callback_list * _M_callbacks
const __ctype_type * _M_ctype
iostate _M_exception
char_type _M_fill
bool _M_fill_init
fmtflags _M_flags
streamsize _M_gcount
locale _M_ios_locale
_Words _M_local_word [_S_local_word_size]
const __num_get_type * _M_num_get
const __num_put_type * _M_num_put
streamsize _M_precision
basic_streambuf< _CharT, _Traits > * _M_streambuf
iostate _M_streambuf_state
basic_ostream< _CharT, _Traits > * _M_tie
streamsize _M_width
_Words * _M_word
int _M_word_size
_Words _M_word_zero

🌈 Friends 🌈

class sentry — that's the whole friend list. just the one. quality over quantity, iykyk.

⭐ Detailed Description ⭐

template<typename _CharT, typename _Traits>
    class std::basic_istream< _CharT, _Traits >

"Template class basic_istream.

🍓 Template Parameters 🍓

_CharT — type of character stream.
_Traits — traits for character type, defaults to char_traits<_CharT>.

This is the base class for all input streams, no cap. It provides text formatting of all builtin types, and it communicates with any class derived from basic_streambuf to do the actual input. so basically she's the main character and the streambuf does the running around behind the scenes 💅

✨ Member Typedef Documentation ✨

template<typename _CharT, typename _Traits> typedef num_put<_CharT, ostreambuf_iterator<_CharT, _Traits> > std::basic_ios< _CharT, _Traits >::__num_put_type [inherited]

These are non-standard types. yeah. non-standard. she's special like that 🎀

typedef void(* std::ios_base::event_callback) (event __e, ios_base &__b, int __i) [inherited]

The type of an event callback function. so this is the shape of a function that gets pinged when stuff goes down.

Parameters, bestie:

__e — one of the members of the event enum.
__b — reference to the ios_base object.
__i — the integer provided when the callback was registered.

Event callbacks are user defined functions that get called during several ios_base and basic_ios functions, specifically imbue(), copyfmt(), and ~ios().

typedef _Ios_Fmtflags std::ios_base::fmtflags [inherited]

This is a bitmask type. _Ios_Fmtflags is implementation-defined, but it is valid to perform bitwise operations on these values and expect the Right Thing to happen. Defined objects of type fmtflags are:

boolalpha
dec
fixed
hex
internal
left
oct
right
scientific
showbase
showpoint
showpos
skipws
unitbuf
uppercase
adjustfield
basefield
floatfield

typedef _Ios_Iostate std::ios_base::iostate [inherited]

This is a bitmask type. _Ios_Iostate is implementation-defined, but it is valid to perform bitwise operations on these values and expect the Right Thing to happen. Defined objects of type iostate are:

badbit
eofbit
failbit
goodbit

typedef _Ios_Openmode std::ios_base::openmode [inherited]

This is a bitmask type. _Ios_Openmode is implementation-defined, but it is valid to perform bitwise operations on these values and expect the Right Thing to happen. Defined objects of type openmode are:

app
ate
binary
in
out
trunc

typedef _Ios_Seekdir std::ios_base::seekdir [inherited]

This is an enumerated type. _Ios_Seekdir is implementation-defined. Defined values of type seekdir are:

beg
cur, equivalent to SEEK_CUR in the C standard library.
end, equivalent to SEEK_END in the C standard library.

🌸 Member Enumeration Documentation 🌸

enum std::ios_base::event [inherited]

The set of events that may be passed to an event callback. erase_event is used during ~ios() and copyfmt(). imbue_event is used during imbue(). copyfmt_event is used during copyfmt(). three lil events, three lil moments, all iconic 💖

💫 Constructor & Destructor Documentation 💫

template<typename _CharT, typename _Traits> std::basic_istream< _CharT, _Traits >::basic_istream (__streambuf_type * __sb) [inline], [explicit]

Base constructor. This ctor is almost never called by the user directly, rather from derived classes' initialization lists, which pass a pointer to their own stream buffer.

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry().

template<typename _CharT, typename _Traits> virtual std::basic_istream< _CharT, _Traits >::~basic_istream () [inline], [virtual]

Base destructor. This does very little apart from providing a virtual base dtor. she's chill like that, does her one job and dips 🦋

🔥 Member Function Documentation 🔥

const locale & std::ios_base::_M_getloc () const [inline], [inherited]

Locale access. she's your plug for the current locale.

Returns: a reference to the current locale.

Like getloc above, but returns a reference instead of generating a copy. so she's the efficient version, no unnecessary copying, very demure.

Referenced by std::money_get< _CharT, _InIter >::do_get(), std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_date(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_time(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::time_get< _CharT, _InIter >::do_get_year(), std::num_put< _CharT, _OutIter >::do_put(), std::time_put< _CharT, _OutIter >::do_put(), std::time_get< _CharT, _InIter >::get(), and std::time_put< _CharT, _OutIter >::put(). literally everyone wants a piece of her.

template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT, _Traits >::bad () const [inline], [nodiscard], [inherited]

Fast error checking. quick lil vibe check on whether things went wrong.

Returns: true if the badbit is set.

heads up: other iostate flags may also be set. so bad() saying true doesn't mean the others are quiet, bestie.

Referenced by std::basic_ostream< _CharT, _Traits >::sentry::sentry().

template<typename _CharT, typename _Traits> void std::basic_ios< _CharT, _Traits >::clear (iostate __state = goodbit) [inherited]

[Re]sets the error state. reset era 🎀

Parameters:

__state — the new state flag(s) to set.

See std::ios_base::iostate for the possible bit values. Most users will not need to pass an argument — the default goodbit is doing the heavy lifting for you.

References std::ios_base::badbit, exceptions(), rdbuf(), and rdstate().

Referenced by:

std::basic_ios< char_type, traits_type >::exceptions()
std::basic_fstream< char >::open()
std::basic_fstream< char >::open()
std::basic_ifstream< char >::open()
std::basic_ifstream< char >::open()
std::basic_ofstream< char >::open()
std::basic_ofstream< char >::open()
std::__detail::operator>>()
std::basic_istream< _CharT, _Traits >::putback()
rdbuf()
std::basic_istream< _CharT, _Traits >::seekg()
std::basic_istream< _CharT, _Traits >::seekg()
std::basic_ios< char_type, traits_type >::setstate()
std::basic_istream< _CharT, _Traits >::unget()

okay bestie yes open() is listed twice per stream and no I did not do a typo, that's literally what the docs say 🫶 moving on.

`copyfmt` — the glow-up montage 💅

template<typename _CharT, typename _Traits> basic_ios< _CharT, _Traits > &
    std::basic_ios< _CharT, _Traits >::copyfmt (const basic_ios< _CharT,
    _Traits > & __rhs) [inherited]

Copies fields of __rhs into this. It's giving "make this stream look exactly like that stream" energy ✨

Parameters

__rhs — The source values for the copies.

Returns

Reference to this object.

So here's the tea: all fields of __rhs get copied into this object, except rdbuf() and rdstate() — those two stay exactly as they were, no touchy 🙅‍♀️. All values in the pword and iword arrays get copied too. Before copying, each callback is invoked with erase_event. After copying, each (new) callback is invoked with copyfmt_event. And the grand finale? The final step is to copy exceptions().

References: basic_ios(), std::__addressof(), exceptions(), fill(), std::ios_base::flags(), std::ios_base::getloc(), std::ios_base::precision(), tie(), std::tie(), and std::ios_base::width().

`eof` — vibe check, but for end-of-file 🌸

template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT,
    _Traits >::eof () const [inline],  [nodiscard],  [inherited]

Fast error checking. Like, speedrun edition 🏃‍♀️

Returns

True if the eofbit is set.

heads up bestie: other iostate flags may also be set. eof being true does NOT mean everything else is chill 😭

`exceptions` (the const one) — mask reveal 👑

template<typename _CharT, typename _Traits> iostate std::basic_ios< _CharT,
    _Traits >::exceptions () const [inline],  [nodiscard],  [inherited]

Throwing exceptions on errors.

Returns

The current exceptions mask.

This changes nothing in the stream — it's a read-only peek, no notes taken 👀. See the one-argument version of exceptions(iostate) for the meaning of the return value.

Referenced by: clear(), and copyfmt().

`exceptions` (the setter one) — now you're setting the mask 💀

template<typename _CharT, typename _Traits> void std::basic_ios< _CharT,
    _Traits >::exceptions (iostate __except) [inline],  [inherited]

Throwing exceptions on errors.

Parameters

__except — The new exceptions mask.

So by default, error flags are set silently. Like, no drama, they just sit there 😶. But you can set an exceptions mask for each stream; if a bit in the mask becomes set in the error flags, then an exception of type std::ios_base::failure is thrown. periodt.

careful babe: if the error flag is already set when the exceptions mask is added, the exception is immediately thrown. no waiting, no chill, instant chaos 🔥

Try running the following under GCC 3.1 or later:

#include <iostream>
#include <fstream>
#include <exception>

int main()
{
    std::set_terminate (__gnu_cxx::__verbose_terminate_handler);

    std::ifstream f ("/etc/motd");

    std::cerr << "Setting badbit\n";
    f.setstate (std::ios_base::badbit);

    std::cerr << "Setting exception mask\n";
    f.exceptions (std::ios_base::badbit);
}

`fail` — another fast error check, we love consistency ✨

template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT,
    _Traits >::fail () const [inline],  [nodiscard],  [inherited]

Fast error checking.

Returns

True if either the badbit or the failbit is set.

Fun little lore drop: checking the badbit in fail() is historical practice 📜. And again — note that other iostate flags may also be set.

Referenced by: std::basic_ios< char_type, traits_type >::operator bool(), std::basic_ios< char_type, traits_type >::operator!(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_istream< _CharT, _Traits >::tellg(), and std::basic_ostream< _CharT, _Traits >::tellp().

`fill` (getter) — the empty character, she's so iconic 🎀

template<typename _CharT, typename _Traits> char_type std::basic_ios<
    _CharT, _Traits >::fill () const [inline],  [nodiscard],  [inherited]

Retrieves the empty character.

Returns

The current fill character.

It defaults to a space (' ') in the current locale. simple as that 🌈

Referenced by: copyfmt(), and std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator<<.

`fill` (setter) — new character just dropped 🦋

template<typename _CharT, typename _Traits> char_type std::basic_ios<
    _CharT, _Traits >::fill (char_type __ch) [inline],  [inherited]

Sets a new empty character.

Parameters

__ch — The new character.

Returns

The previous fill character.

Okay so here's when the fill character even matters: it's used to fill out space when P+ characters have been requested (e.g., via setw), Q characters are actually used, and Q<P. And yeah, it defaults to a space (' ') in the current locale.

`flags` (getter) — format flags, come get y'all 🧚

fmtflags std::ios_base::flags () const [inline],  [nodiscard],  [inherited]

Access to format flags.

Returns

The format control flags for both input and output.

Referenced by: std::basic_ios< _CharT, _Traits >::copyfmt(), std::num_get< _CharT, _InIter >::do_get(), std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), std::num_put< _CharT, _OutIter >::do_put(), std::chrono::operator<<(), std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator<<, std::__detail::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), and std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator>>.

(yes that's a lot of std::operator>>() in a row. the docs said it, I said it, we move 💀)

`flags` (setter) — swap the whole vibe in one go 💅

fmtflags std::ios_base::flags (fmtflags __fmtfl) [inline],  [inherited]

Setting new format flags all at once.

Parameters

__fmtfl — The new flags to set.

Returns

The previous format control flags.

heads up: this function overwrites all the format flags with __fmtfl. it's not a merge, it's a full replace, no survivors 🔥

`gcount` — how many characters did we just eat? 🍓

template<typename _CharT, typename _Traits> streamsize std::basic_istream<
    _CharT, _Traits >::gcount () const [inline]

Character counting.

Returns

The number of characters extracted by the previous unformatted input function dispatched for this stream.

`get` — simple extraction 🎀

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits
    >::int_type std::basic_istream< _CharT, _Traits >::get (void )

Simple extraction.

Returns

A character, or eof().

Tries to extract a character. If none are available, sets failbit and returns traits::eof().

References: _M_gcount, std::ios_base::badbit, std::ios_base::eofbit, std::ios_base::failbit, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), and std::basic_ios< _CharT, _Traits >::setstate().

Referenced by: std::basic_istream< char_type, traits_type >::get(), and std::basic_istream< char_type, traits_type >::get().

`get` — extraction into another streambuf 🦋

template<typename _CharT, typename _Traits> __istream_type &
    std::basic_istream< _CharT, _Traits >::get (__streambuf_type & __sb)
    [inline]

Extraction into another streambuf.

Parameters

__sb — A streambuf in which to store data.

Returns

*this

Returns get(__sb,widen('\n')). cute little delegation moment ✨

`get` — extraction into another streambuf, with a stop character 🌸

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits >
    & std::basic_istream< _CharT, _Traits >::get (__streambuf_type & __sb,
    char_type __delim)

Extraction into another streambuf.

Parameters

__sb — A streambuf in which to store data.
__delim — A "stop" character.

Returns

*this

Characters are extracted and inserted into __sb until one of the following happens:

the input sequence reaches EOF
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted)
the next character equals __delim (in this case, the character is not extracted)
an exception occurs (and in this case is caught)

if no characters are stored, failbit is set in the stream's error state. 😭

References: _M_gcount, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), and std::basic_streambuf< _CharT, _Traits >::sgetc().

`get` — simple extraction, single character 🎀

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits >
    & std::basic_istream< _CharT, _Traits >::get (char_type & __c)

Simple extraction.

Parameters

__c — The character in which to store data.

Returns

*this

Tries to extract a character and store it in __c. If none are available, sets failbit and returns traits::eof().

Note: This function is not overloaded on signed char and unsigned char. like, at all. don't come for me 🙈

`get` — multiple characters, go off 👑

template<typename _CharT, typename _Traits> __istream_type &
    std::basic_istream< _CharT, _Traits >::get (char_type * __s, streamsize
    __n) [inline]

Simple multiple-character extraction.

Parameters

__s — Pointer to an array.
__n — Maximum number of characters to store in s.

Returns

*this

Returns get(__s,__n,widen('\n')). again with the delegation, we love a wrapper 💜

`get` — multiple characters with a stop character 🌈

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits >
    & std::basic_istream< _CharT, _Traits >::get (char_type * __s,
    streamsize __n, char_type __delim)

Simple multiple-character extraction.

Parameters

__s — Pointer to an array.
__n — Maximum number of characters to store in __s.
__delim — A "stop" character.

Returns

*this

Characters are extracted and stored into __s until one of the following happens:

__n-1 characters are stored
the input sequence reaches EOF
the next character equals __delim, in which case the character is not extracted

if no characters are stored, failbit is set in the stream's error state. 💀

And in any case, a null character is stored into the next location in the array. always. no exceptions bestie.

Note: This function is not overloaded on signed char and unsigned char.

References: _M_gcount, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), and std::basic_streambuf< _CharT, _Traits >::sgetc().

`getline` — string extraction, the moment we've all been waiting for ✨

template<typename _CharT, typename _Traits> __istream_type &
    std::basic_istream< _CharT, _Traits >::getline (char_type * __s,
    streamsize __n) [inline]

String extraction.

Parameters

__s — A character array in which to store the data.
__n — Maximum number of characters to extract.

Returns

*this

Returns getline(__s,__n,widen('\n')).

`getline` — the `char` specialization 🌟

basic_istream< char > & std::basic_istream< char >::getline (char_type *
    __s, streamsize __n, char_type __delim)

Explicit specialization declarations, defined in src/istream.cc. that's the whole thing, she's special and she knows it 💅

`getline` — the template one, back at it again 🫶

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits >
    & std::basic_istream< _CharT, _Traits >::getline (char_type * __s,
    streamsize __n, char_type __delim)

String extraction.

Parameters

__s — a character array in which to store the data 💾
__n — maximum number of characters to extract
__delim — a "stop" character 🛑

Returns

*this 🫶

So it extracts and stores characters into __s until one of the following happens. And bestie, note that these criteria are required to be tested in the order listed here — that's the whole reason an input line can exactly fill the __s array without setting failbit. Order is the moment, ok? 👑

the input sequence reaches end-of-file, in which case eofbit is set in the stream error state
the next character equals __delim, in which case the character is extracted (and therefore counted in gcount()) but not stored
__n-1 characters are stored, in which case failbit is set in the stream error state

If no characters are extracted, failbit is set. (An empty line of input should therefore not cause failbit to be set — which is honestly so valid of it. 🌸)

In any case, a null character is stored in the next location in the array. 🎀

Referenced by std::basic_istream< char_type, traits_type >::getline().

`locale std::ios_base::getloc () const` `[inline]`, `[nodiscard]`, `[inherited]`

Locale access. 🌍

Returns

A copy of the current locale.

So if imbue(loc) has previously been called, then this function returns loc. Otherwise, it returns a copy of std::locale(), the global C++ locale. Either way you get a locale, periodt.

Referenced by std::basic_ios< _CharT, _Traits >::copyfmt(), std::money_put< _CharT, _OutIter >::do_put(), std::basic_ios< _CharT, _Traits >::imbue(), std::chrono::operator<<(), std::operator>>(), std::operator>>(), and std::ws().

`template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT, _Traits >::good () const` `[inline]`, `[nodiscard]`, `[inherited]`

Fast error checking. ⚡

Returns

True if no error flags are set.

It's literally just a wrapper around rdstate. Simple. Clean. Iconic. 💅

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::basic_ostream< _CharT, _Traits >::sentry::sentry(), and std::__detail::operator>>().

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (void )`

Simple extraction.

Returns

A character, or eof().

Tries to extract a character. If none are available, it sets failbit and returns traits::eof().

References _M_gcount, std::ios_base::eofbit, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), and std::basic_streambuf< _CharT, _Traits >::sbumpc().

Referenced by std::basic_istream< char_type, traits_type >::ignore().

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (streamsize __n)`

Simple extraction.

Returns

A character, or eof().

Tries to extract a character. If none are available, it sets failbit and returns traits::eof().

References _M_gcount, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), and std::basic_streambuf< _CharT, _Traits >::sgetc().

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::ignore (streamsize n, char delim)` `[inline]`

Simple extraction.

Returns

A character, or eof().

Tries to extract a character. If none are available, it sets failbit and returns traits::eof().

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (streamsize __n, int_type __delim)`

Discarding characters. 🗑️✨

Parameters

__n — number of characters to discard
__delim — a "stop" character

Returns

*this

Extracts characters and throws them away until one of the following happens:

if __n != std::numeric_limits<int>::max(), __n characters are extracted
the input sequence reaches end-of-file
the next character equals __delim (in this case, the character is extracted); note that this condition will never occur if __delim equals traits::eof()

NB: Provide four overloads, instead of the single function (with defaults) mandated by the Standard: this leads to a better performing implementation, while still conforming to the Standard. 💀 not them optimizing the overloads

References _M_gcount, and std::ios_base::goodbit.

`template<typename _CharT, typename _Traits> locale std::basic_ios< _CharT, _Traits >::imbue (const locale & __loc)` `[inherited]`

Moves to a new locale. 🦋

Parameters

__loc — the new locale

Returns

The previous locale.

Calls ios_base::imbue(loc), and if a stream buffer is associated with this stream, calls that buffer's pubimbue(loc).

Additional l10n notes are at https://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html

References std::ios_base::getloc(), std::ios_base::imbue(), and rdbuf().

Referenced by std::chrono::operator<<().

`template<typename _CharT, typename _Traits> void std::basic_ios< _CharT, _Traits >::init (basic_streambuf< _CharT, _Traits > * __sb)` `[protected]`, `[inherited]`

All setup is performed here. This is called from the public constructor. It is not virtual and cannot be redefined. 🚫 (main character energy, refuses to be overridden)

`long & std::ios_base::iword (int __ix)` `[inline]`, `[inherited]`

Access to integer array. 🔢

Parameters

__ix — index into the array

Returns

A reference to an integer associated with the index.

The iword function provides access to an array of integers that can be used for any purpose. The array grows as required to hold the supplied index. All integers in the array are initialized to 0.

The implementation reserves several indices. You should use xalloc to obtain an index that is safe to use. Also note that since the array can grow dynamically, it is not safe to hold onto the reference. 🙈 don't be out here keeping stale refs bestie

References iword().

Referenced by iword().

`template<typename _CharT, typename _Traits> char std::basic_ios< _CharT, _Traits >::narrow (char_type c, char dfault) const` `[inline]`, `[inherited]`

Squeezes characters. 🧚

Parameters

__c — the character to narrow
__dfault — the character to narrow

Returns

The narrowed character.

Maps a character of char_type to a character of char, if possible.

Returns the result of

std::use_facet<ctype<char_type> >(getloc()).narrow(c,dfault)

Additional l10n notes are at https://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html

`template<typename _CharT, typename _Traits> std::basic_ios< _CharT, _Traits >::operator bool () const` `[inline]`, `[explicit]`, `[nodiscard]`, `[inherited]`

The quick-and-easy status check. This allows you to write constructs such as if (!a_stream) ... and while (a_stream) ... 🌈

`template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT, _Traits >::operator! () const` `[inline]`, `[nodiscard]`, `[inherited]`

The quick-and-easy status check. This allows you to write constructs such as if (!a_stream) ... and while (a_stream) ... 🌈

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (__ios_type &(* pf )(ios_type &))` `[inline]`

Interface for manipulators. 🎛️ Manipulators such as std::ws and std::dec use these functions in constructs like std::cin >> std::ws. For more information, see the iomanip header.

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (__istream_type &(* pf )(istream_type &))` `[inline]`

Interface for manipulators. 🎛️ Manipulators such as std::ws and std::dec use these functions in constructs like std::cin >> std::ws. For more information, see the iomanip header.

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::operator>> (__streambuf_type * __sb)`

Extracting into another streambuf. 🚰

Parameters

__sb — a pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If __sb is NULL, the stream will set failbit in its error state. 💀

Characters are extracted from this stream and inserted into the __sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

References std::ios_base::eofbit, std::ios_base::failbit, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), and std::basic_ios< _CharT, _Traits >::setstate().

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (bool & __n)` `[inline]`

Integer arithmetic extractors. 🔢

Parameters

__n — a variable of builtin integral type

Returns

*this if successful

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data. 🍓

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (double & __f)` `[inline]`

Floating point arithmetic extractors. 🧮

Parameters

__f — a variable of builtin floating point type

Returns

*this if successful

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data. 🍓

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (float & __f)` `[inline]`

Floating point arithmetic extractors. 🧮

Parameters

__f — a variable of builtin floating point type

Returns

*this if successful

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data. 🍓

okay so literally every one of these extractors parses your input using the stream's current locale — specifically the num_get facet. that's the whole vibe, no cap. 💅

🌟 `operator>>` (int) — integer arithmetic extractor

template<typename _CharT, typename _Traits>
basic_istream<_CharT, _Traits>&
std::basic_istream<_CharT, _Traits>::operator>>(int& __n)

Integer arithmetic extractors. bestie these are the moment ✨

Parameters

__n — a variable of builtin integral type 🫶

Returns

*this if successful 💖

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

🎀 `operator>>` (manipulators) — `ios_base &(__pf)(ios_base &)` — [inline]*

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(ios_base& (*__pf)(ios_base&))

Interface for manipulators. manipulators like std::ws and std::dec use these functions in constructs such as std::cin >> std::ws. wanna know more? go peek at the iomanip header, iykyk 👑

🦋 `operator>>` (long) — [inline]

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(long& __n)

Integer arithmetic extractors.

Parameters

__n — a variable of builtin integral type 🌸

Returns

*this if successful ⭐

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

🍓 `operator>>` (long double) — [inline]

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(long double& __f)

Floating point arithmetic extractors. yes girl, floats get their own little corner 💅

Parameters

__f — a variable of builtin floating point type 🎀

Returns

*this if successful 💖

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

💜 `operator>>` (long long) — [inline]

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(long long& __n)

Integer arithmetic extractors.

Parameters

__n — a variable of builtin integral type ✨

Returns

*this if successful 🔥

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

🌈 `operator>>` (short)

template<typename _CharT, typename _Traits>
basic_istream<_CharT, _Traits>&
std::basic_istream<_CharT, _Traits>::operator>>(short& __n)

Integer arithmetic extractors.

Parameters

__n — a variable of builtin integral type 🫶

Returns

*this if successful 🌟

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

References — std::ios_base::badbit, std::ios_base::failbit, std::num_get< _CharT, _InIter >::get(), std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::setstate(), and std::use_facet(). 📚

💖 `operator>>` (unsigned int) — [inline]

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(unsigned int& __n)

Integer arithmetic extractors.

Parameters

__n — a variable of builtin integral type 🧚

Returns

*this if successful 💅

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

🎀 `operator>>` (unsigned long) — [inline]

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(unsigned long& __n)

Integer arithmetic extractors.

Parameters

__n — a variable of builtin integral type 🌸

Returns

*this if successful ⭐

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

🦋 `operator>>` (unsigned long long) — [inline]

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(unsigned long long& __n)

Integer arithmetic extractors.

Parameters

__n — a variable of builtin integral type 💜

Returns

*this if successful ✨

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

💅 `operator>>` (unsigned short) — [inline]

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(unsigned short& __n)

Integer arithmetic extractors.

Parameters

__n — a variable of builtin integral type 🍓

Returns

*this if successful 🔥

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

👑 `operator>>` (void) — [inline]*

template<typename _CharT, typename _Traits>
__istream_type&
std::basic_istream<_CharT, _Traits>::operator>>(void*& __p)

Basic arithmetic extractors. pointers get to play too, periodt 💅

Parameters

__p — a variable of pointer type 🫶

Returns

*this if successful 💖

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

🔥 `peek` — looking ahead in the stream

template<typename _CharT, typename _Traits>
basic_istream<_CharT, _Traits>::int_type
std::basic_istream<_CharT, _Traits>::peek(void)

Looking ahead in the stream. the main character move of glancing before you commit 💫

Returns

the next character, or eof(). 😭

so like — after constructing the sentry object, if good() is false, it returns traits::eof(). otherwise it reads but does not extract the next input character. peek don't snatch, bestie 🙈

References — _M_gcount, std::ios_base::goodbit, and std::basic_ios< _CharT, _Traits >::rdbuf(). 📚

🌸 `std::ios_base::precision()` — [inline], [nodiscard], [inherited]

streamsize std::ios_base::precision() const

Flags access.

Returns

the precision to generate on certain output operations. ✨

⚠️ be careful if you try to give a definition of precision here — see DR 189. no cap, this one's a trap 🚩

Referenced by std::basic_ios< _CharT, _Traits >::copyfmt(), and std::chrono::operator<<(). 💜

🧚 `std::ios_base::precision(streamsize __prec)` — [inline], [inherited]

streamsize std::ios_base::precision(streamsize __prec)

Changing flags.

Parameters

__prec — the new precision value 🎀

Returns

the previous value of precision(). ⭐

🎀 `putback` — unextracting a single character

template<typename _CharT, typename _Traits>
basic_istream<_CharT, _Traits>&
std::basic_istream<_CharT, _Traits>::putback(char_type __c)

Unextracting a single character. it's giving "jk bestie, put it back" 💅

Parameters

__c — the character to push back into the input stream 🫶

Returns

*this 💖

if rdbuf() is not null, it calls rdbuf()->sputbackc(c).

if rdbuf() is null, or if sputbackc() fails, it sets badbit in the error state. 😭

📌 Note — this function first clears eofbit. since no characters are extracted, the next call to gcount() will return 0, as required by DR 60. iconic behaviour honestly ✨

References — _M_gcount, std::ios_base::badbit, std::basic_ios< _CharT, _Traits >::clear(), std::ios_base::eofbit, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), std::basic_ios< _CharT, _Traits >::rdstate(), std::basic_ios< _CharT, _Traits >::setstate(), and std::basic_streambuf< _CharT, _Traits >::sputbackc(). 📚

Referenced by std::operator<<(). 💜

🦋 `std::ios_base::pword(int __ix)` — [inline], [inherited]

void*& std::ios_base::pword(int __ix)

Access to void pointer array.

Parameters

__ix — index into the array 🌸

Returns

a reference to a void* associated with the index. ⭐

so the pword function provides access to an array of pointers that can be used for any purpose. the array grows as required to hold the supplied index, and all pointers in the array are initialized to 0. 🫶

🚩 the implementation reserves several indices. you should use xalloc to obtain an index that is safe to use. also note that since the array can grow dynamically, it is not safe to hold onto the reference. lowkey important, don't skip this one bestie 😭

💜 `std::basic_ios< _CharT, _Traits >::rdbuf() const` — [inline], [nodiscard], [inherited]

template<typename _CharT, typename _Traits>
basic_streambuf<_CharT, _Traits>*
std::basic_ios<_CharT, _Traits>::rdbuf() const

Accessing the underlying buffer.

Returns

the current stream buffer. 👑

this does not change the state of the stream. no drama, no side effects ✨

Referenced by clear(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::getline(), std::getline(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, _Traits >::ignore(), imbue(), std::operator<<(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), std::tr2::operator>>(), std::basic_istream< _CharT, _Traits >::peek(), std::basic_ostream< _CharT, _Traits >::put(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_istream< _CharT, _Traits >::sync(), std::basic_istream< _CharT, _Traits >::tellg(), std::basic_ostream< _CharT, _Traits >::tellp(), std::basic_istream< _CharT, _Traits >::unget(), and std::ws(). that's a LOT of friends, main character energy fr fr 💅📚

🎀 `std::basic_ios< _CharT, _Traits >::rdbuf(basic_streambuf< _CharT, _Traits > * __sb)` — [inherited]

template<typename _CharT, typename _Traits>
basic_streambuf<_CharT, _Traits>*
std::basic_ios<_CharT, _Traits>::rdbuf(basic_streambuf<_CharT, _Traits>* __sb)

Changing the underlying buffer.

Parameters

__sb — the new stream buffer 🌸

Returns

the previous stream buffer. ⭐

it associates a new buffer with the current stream, and clears the error state. ✨

💀 okay so, due to historical accidents which the LWG refuses to correct, the I/O library suffers from a design error: this function is hidden in derived classes by overrides of the zero-argument rdbuf(), which is non-virtual for hysterical raisins. as a result, you must use explicit qualifications to access this function via any derived class. for example:

std::fstream     foo;         // or some other derived type
std::streambuf*  p = .....;

foo.ios::rdbuf(p);            // ios == basic_ios<char>

References — clear(). 📚

🧚 `std::basic_ios< _CharT, _Traits >::rdstate() const` — [inline], [nodiscard], [inherited]

template<typename _CharT, typename _Traits>
iostate
std::basic_ios<_CharT, _Traits>::rdstate() const

Returns the error state of the stream buffer.

Returns

a bit pattern (well, isn't everything?) 😭💅

see std::ios_base::iostate for the possible bit values. most users will call one of the interpreting wrappers, e.g., good(). 🫶

Referenced by std::basic_ios< char_type, traits_type >::bad(), clear(), std::basic_ios< char_type, traits_type >::eof(), std::basic_ios< char_type, traits_type >::fail(), std::basic_ios< char_type, traits_type >::good(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_ios< char_type, traits_type >::setstate(), and std::basic_istream< _CharT, _Traits >::unget(). 📚

🌈 `read` — extraction without delimiters

template<typename _CharT, typename _Traits>
basic_istream<_CharT, _Traits>&
std::basic_istream<_CharT, _Traits>::read(char_type* __s, streamsize __n)

Extraction without delimiters. it takes exactly what you ask for, no negotiating ✨

Parameters

__s — a character array 🌸
__n — maximum number of characters to store 🎀

Returns

*this 💖

okay so back to read — when the stream state is good(), it pulls characters out and drops them into __s until one of these things happens:

__n characters have been stored
the input sequence hits end-of-file, in which case the error state gets set to failbit|eofbit.

Note bestie 📌 this function is not overloaded on signed char and unsigned char.

`streamsize std::basic_istream<_CharT, _Traits>::readsome(char_type * s, streamsize n)`

Extraction until the buffer is exhausted, but no more. like… it takes what's there and dips, no begging for more 💅

Parameters

__s — a character array.
__n — maximum number of characters to store.

Returns

The number of characters extracted.

So it extracts characters and stores them into __s, and how many it takes depends on how many characters are left sitting in the streambuf's buffer, rdbuf()->in_avail(), which we're calling A here:

if A == -1, it sets eofbit and extracts no characters
if A == 0, it extracts no characters
if A > 0, it extracts min(A,n)

The goal is literally to empty the current buffer and not request anything more from the external input sequence that the streambuf is controlling. main character energy of just taking what's already on the table 🍓

References: _M_gcount, std::ios_base::badbit, std::ios_base::eofbit, std::ios_base::goodbit, std::min(), std::basic_ios< _CharT, _Traits >::rdbuf(), std::basic_ios< _CharT, _Traits >::setstate().

`void std::ios_base::register_callback(event_callback fn, int index)`

[inherited] — Add the callback __fn with parameter __index. 🎀

Parameters

__fn — the function to add.
__index — the integer to pass to the function when invoked.

So it registers a function as an event callback, with an integer parameter that gets passed to the function whenever it's invoked. Multiple copies of the same function are allowed, no gatekeeping here. And if there are multiple callbacks, they get invoked in the order they were registered — first come, first served, periodt. ✨

`basic_istream< _CharT, _Traits > & std::basic_istream<_CharT, _Traits>::seekg(off_type __off, ios_base::seekdir __dir)`

Changing the current read position. glow-up for your cursor position 💫

Parameters

__off — a file offset object.
__dir — the direction in which to seek.

Returns

*this

If fail() is not true, it calls rdbuf()->pubseekoff(__off,__dir). And if that function fails, it sets failbit. rude but okay 😭

Note — this function first clears eofbit. It does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount().

References: std::ios_base::badbit, std::basic_ios< _CharT, _Traits >::clear(), std::ios_base::eofbit, std::basic_ios< _CharT, _Traits >::fail(), std::ios_base::failbit, std::ios_base::goodbit, std::ios_base::in, std::basic_ios< _CharT, _Traits >::rdbuf(), std::basic_ios< _CharT, _Traits >::rdstate(), std::basic_ios< _CharT, _Traits >::setstate().

`basic_istream< _CharT, _Traits > & std::basic_istream<_CharT, _Traits>::seekg(pos_type __pos)`

Changing the current read position. the other flavor of the same vibe 🌸

Parameters

__pos — a file position object.

Returns

*this

If fail() is not true, it calls rdbuf()->pubseekpos(__pos). If that function fails, it sets failbit. same energy as before, different arg 🫶

Note — this function first clears eofbit. It does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount().

`fmtflags std::ios_base::setf(fmtflags __fmtfl)`

[inline], [inherited] — Setting new format flags. 🔥

Parameters

__fmtfl — additional flags to set.

Returns

The previous format control flags.

This one sets additional flags in format control, and here's the tea: flags that were previously set stay set. no clearing, no erasing, we're just adding 💅

Referenced by std::__detail::operator>>().

`fmtflags std::ios_base::setf(fmtflags fmtfl, fmtflags mask)`

[inline], [inherited] — Setting new format flags. ✨

Parameters

__fmtfl — additional flags to set.
__mask — the flags mask for __fmtfl.

Returns

The previous format control flags.

This version clears mask in the format flags, then sets fmtfl & mask. An example mask is ios_base::adjustfield. it's giving precision, it's giving control 🎀

`void std::basic_ios<_CharT, _Traits>::setstate(iostate __state)`

[inline], [inherited] — Sets additional flags in the error state. 💀

Parameters

__state — the additional state flag(s) to set.

See std::ios_base::iostate for the possible bit values.

Referenced by std::basic_ostream< _CharT, _Traits >::sentry::sentry(), std::basic_fstream< char >::close(), std::basic_ifstream< char >::close(), std::basic_ofstream< char >::close(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::getline(), std::getline(), std::basic_fstream< char >::open(), std::basic_fstream< char >::open(), std::basic_ifstream< char >::open(), std::basic_ifstream< char >::open(), std::basic_ofstream< char >::open(), std::basic_ofstream< char >::open(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::operator<<(), std::operator<<(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::operator>>(), std::operator>>(), std::tr2::operator>>(), std::basic_ostream< _CharT, _Traits >::put(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_istream< _CharT, _Traits >::sync(), std::ws().

ngl that's a whole friend group showing up to the party 🎉

`int std::basic_istream<_CharT, _Traits>::sync(void)`

Synchronizing the stream buffer. 🦋

Returns

0 on success, -1 on failure

Here's the flow, bestie:

If rdbuf() is a null pointer, it returns -1.
Otherwise, it calls rdbuf()->pubsync(), and if that returns -1, it sets badbit and returns -1.
Otherwise, it returns 0.

Note — this function does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount().

References: std::ios_base::badbit, std::ios_base::goodbit, std::basic_streambuf< _CharT, _Traits >::pubsync(), std::basic_ios< _CharT, _Traits >::rdbuf(), std::basic_ios< _CharT, _Traits >::setstate().

`bool std::ios_base::sync_with_stdio(bool __sync = true)`

[static], [inherited] — Interaction with the standard C I/O objects. 🌈

Parameters

__sync — whether to synchronize or not.

Returns

True if the standard streams were previously synchronized.

The synchronization referred to is only that between the standard C facilities (e.g., stdout) and the standard C++ objects (e.g., cout). User-declared streams are unaffected. See https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary

iykyk — this is the one people turn off for speed and then act surprised 😭

`basic_istream< _CharT, _Traits >::pos_type std::basic_istream<_CharT, _Traits>::tellg(void)`

Getting the current read position. ⭐

Returns

A file position object.

If fail() is not false, it returns pos_type(-1) to indicate failure. Otherwise it returns rdbuf()->pubseekoff(0,cur,in).

Note — this function does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount(). At variance with putback, unget and seekg, eofbit is not cleared first. 🙈

References: std::ios_base::badbit, std::ios_base::cur, std::basic_ios< _CharT, _Traits >::fail(), std::ios_base::in, std::basic_ios< _CharT, _Traits >::rdbuf().

`basic_ostream< _CharT, _Traits > * std::basic_ios<_CharT, _Traits>::tie() const`

[inline], [nodiscard], [inherited] — Fetches the current tied stream. 🫶

Returns

A pointer to the tied stream, or NULL if the stream is not tied.

So a stream may be tied (or synchronized) to a second output stream. When this stream performs any I/O, the tied stream gets flushed first. For example, std::cin is tied to std::cout. iconic behavior, honestly 👑

Referenced by std::basic_ostream< _CharT, _Traits >::sentry::sentry(), and copyfmt().

`basic_ostream< _CharT, _Traits > * std::basic_ios<_CharT, _Traits>::tie(basic_ostream< _CharT, _Traits > * __tiestr)`

[inline], [inherited] — Ties this stream to an output stream. 🎀

Parameters

__tiestr — the output stream.

Returns

The previously tied output stream, or NULL if the stream was not tied.

This sets up a new tie; see tie() for more. besties are linked now 💖

`basic_istream< _CharT, _Traits > & std::basic_istream<_CharT, _Traits>::unget(void)`

Unextracting the previous character. the rewind, the take-backsies 💫

Returns

*this

Here's what goes down:

If rdbuf() is not null, it calls rdbuf()->sungetc(c).
If rdbuf() is null or if sungetc() fails, it sets badbit in the error state.

Note — this function first clears eofbit. Since no characters are extracted, the next call to gcount() will return 0, as required by DR 60.

References: _M_gcount, std::ios_base::badbit, std::basic_ios< _CharT, _Traits >::clear(), std::ios_base::eofbit, std::ios_base::goodbit, std::basic_ios< _CharT, _Traits >::rdbuf(), std::basic_ios< _CharT, _Traits >::rdstate(), std::basic_streambuf< _CharT, _Traits >::sungetc().

Referenced by std::__detail::operator>>().

`void std::ios_base::unsetf(fmtflags __mask)`

[inline], [inherited] — Clearing format flags. 🧚

Parameters

__mask — the flags to unset.

This function clears __mask in the format flags. the un-slay of flags, if you will 💅

`char_type std::basic_ios<_CharT, _Traits>::widen(char __c) const`

[inline], [inherited] — Widens characters. 🌸

Parameters

__c — the character to widen.

Returns

The widened character.

It maps a character of char to a character of char_type. And it returns the result of

std::use_facet<ctype<char_type> >(getloc()).widen(c)

Additional l10n notes are at https://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html 🌍

widen the vibe, bestie, the locale said so ✨

Referenced by std::endl(), std::basic_ios< char_type, traits_type >::fill(), std::basic_istream< char_type, traits_type >::get(), std::basic_istream< char_type, traits_type >::get(), std::basic_istream< char_type, traits_type >::getline(), std::getline(), std::getline(), std::operator<<(), std::operator<<(), std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator<<, and std::tr2::operator>>().

`streamsize std::ios_base::width () const` — `[inline]`, `[nodiscard]`, `[inherited]`

okay bestie this one is literally called Flags access and it's giving "how wide should my output be" energy ✨

Returns

The minimum field width to generate on output operations. 🎀

And just so we're clear — minimum field width means the number of characters. That's the unit. Characters. Not vibes. 😭

Referenced by std::basic_ios< _CharT, _Traits >::copyfmt(), std::num_put< _CharT, _OutIter >::do_put(), std::operator>>(), and std::operator>>().

`streamsize std::ios_base::width (streamsize __wide)` — `[inline]`, `[inherited]`

This is the Changing flags twin, the setter of the duo 💅

Parameters

__wide — the new width value, bestie. That's the whole assignment.

Returns

The previous value of width(). Not the new one. The old one. She remembers where you were before she changed. iconic behavior tbh 👑

`int std::ios_base::xalloc ()` — `[static]`, `[inherited]`

Access to unique indices ✨ and honestly this one is so underrated.

Returns

An integer different from all previous calls. every. single. time. no cap 🫶

This function returns a unique integer every time it is called. It can be used for any purpose, but is primarily intended to be a unique index for the iword and pword functions. The expectation is that an application calls xalloc in order to obtain an index in the iword and pword arrays that can be used without fear of conflict. 🦋

The implementation maintains a static variable that is incremented and returned on each invocation. And xalloc is guaranteed to return an index that is safe to use in the iword and pword arrays. slay, no notes 💖

🎀 Member Data Documentation 🎀

okay these are the actual data members, the little variables living inside these classes. buckle up, there are a LOT of them and they're all lowkey important 🙈

`template<typename _CharT, typename _Traits> streamsize std::basic_istream< _CharT, _Traits >::_M_gcount` — `[protected]`

The number of characters extracted in the previous unformatted function; see gcount(). that's it, that's the whole job, she counts 🧮

Referenced by get(), get(), get(), get(), ignore(), ignore(), ignore(), peek(), putback(), read(), readsome(), and unget().

`const fmtflags std::ios_base::adjustfield` — `[static]`, `[inherited]`

A mask of left|right|internal. Useful for the 2-arg form of setf. a little trio of alignment besties 💅

Referenced by std::num_put< _CharT, _OutIter >::do_put(), std::internal(), std::left(), and std::right().

`const openmode std::ios_base::app` — `[static]`, `[inherited]`

Seek to end before each write. every write. she checks. she does not skip. 📍

Referenced by std::basic_filebuf< char_type, traits_type >::_M_set_buffer(), std::basic_filebuf< _CharT, _Traits >::overflow(), and std::basic_filebuf< _CharT, _Traits >::xsputn().

`const openmode std::ios_base::ate` — `[static]`, `[inherited]`

Open and seek to end immediately after opening. note the difference from app bestie — ate does it once at open time, app does it before every single write. not the same girl, don't mix them up 💀

Referenced by std::basic_filebuf< _CharT, _Traits >::open().

`const iostate std::ios_base::badbit` — `[static]`, `[inherited]`

Indicates a loss of integrity in an input or output sequence (such as an irrecoverable read error from a file). this is the bad one, the serious one, the "we are cooked" bit 😭

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::basic_ostream< _CharT, _Traits >::sentry::~sentry(), std::basic_ios< _CharT, _Traits >::clear(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_iostream< char_type, traits_type >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_iostream< char_type, traits_type >::operator<<(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::basic_ostream< _CharT, _Traits >::put(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, char_traits< _CharT > >::read(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::sync(), std::basic_istream< _CharT, _Traits >::tellg(), std::basic_istream< _CharT, _Traits >::unget(), and std::ws().

`const fmtflags std::ios_base::basefield` — `[static]`, `[inherited]`

A mask of dec|oct|hex. Useful for the 2-arg form of setf. your number base squad, choose your fighter 🔢

Referenced by std::dec(), std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), std::hex(), and std::oct().

`const seekdir std::ios_base::beg` — `[static]`, `[inherited]`

Request a seek relative to the beginning of the stream. back to the start, babes 🎬

Referenced by std::basic_filebuf< _CharT, _Traits >::seekpos().

`const openmode std::ios_base::binary` — `[static]`, `[inherited]`

Perform input and output in binary mode (as opposed to text mode). And then the manpage hits you with this:

This is probably not what you think it is; see https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary.

no fr bestie, go read that doc before you assume anything. the manpage is literally telling you your mental model is wrong 💀

Referenced by std::basic_filebuf< _CharT, _Traits >::showmanyc().

`const fmtflags std::ios_base::boolalpha` — `[static]`, `[inherited]`

Insert/extract bool in alphabetic rather than numeric format. so you get true/false instead of 1/0. she's fancy like that ✨

Referenced by std::boolalpha(), std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), and std::noboolalpha().

`const seekdir std::ios_base::cur` — `[static]`, `[inherited]`

Request a seek relative to the current position within the sequence. right where you are, right now, no moving 🫶

Referenced by std::basic_filebuf< _CharT, _Traits >::imbue(), std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_filebuf< _CharT, _Traits >::pbackfail(), std::basic_filebuf< _CharT, _Traits >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_istream< _CharT, _Traits >::tellg(), and std::basic_ostream< _CharT, _Traits >::tellp().

`const fmtflags std::ios_base::dec` — `[static]`, `[inherited]`

Converts integer input or generates integer output in decimal base. the default one, the base-10 girlie, the one everyone uses without thinking 🌸

Referenced by std::dec(), std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator<<, and std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator>>.

`const seekdir std::ios_base::end` — `[static]`, `[inherited]`

Request a seek relative to the current end of the sequence. run to the back of the line 🏃‍♀️

Referenced by std::basic_filebuf< _CharT, _Traits >::open(), and std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff().

`const iostate std::ios_base::eofbit` — `[static]`, `[inherited]`

Indicates that an input operation reached the end of an input sequence. that's all folks, nothing left to read 🎀

Referenced by std::num_get< _CharT, _InIter >::do_get(), std::num_get< _CharT, _InIter >::do_get(), std::num_get< _CharT, _InIter >::do_get(), std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_date(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_time(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::time_get< _CharT, _InIter >::do_get_year(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::time_get< _CharT, _InIter >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::basic_istream< _CharT, char_traits< _CharT > >::peek(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, char_traits< _CharT > >::seekg(), std::basic_istream< _CharT, _Traits >::unget(), std::basic_istream< _CharT, char_traits< _CharT > >::unget(), and std::ws().

`const iostate std::ios_base::failbit` — `[static]`, `[inherited]`

Indicates that an input operation failed to read the expected characters, or that an output operation failed to generate the desired characters. not the catastrophic one like badbit, but still a fail, still a whole mood 😔

Referenced by std::basic_ostream< _CharT, _Traits >::sentry::sentry(), std::basic_fstream< char >::close(), std::basic_ifstream< char >::close(), std::basic_ofstream< char >::close(), std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::time_get< _CharT, _InIter >::do_get_year(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::time_get< _CharT, _InIter >::get(), std::basic_fstream< char >::open(), std::basic_fstream< char >::open(), std::basic_ifstream< char >::open(), std::basic_ifstream< char >::open(), std::basic_ofstream< char >::open(), std::basic_ofstream< char >::open(), std::operator<<(), std::basic_iostream< char_type, traits_type >::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), and std::basic_ostream< _CharT, _Traits >::seekp().

`const fmtflags std::ios_base::fixed` — `[static]`, `[inherited]`

Generate floating-point output in fixed-point notation. no exponents, just decimals, very demure 🎀

Referenced by std::fixed(), and std::hexfloat().

`const fmtflags std::ios_base::floatfield` — `[static]`, `[inherited]`

A mask of scientific|fixed. Useful for the 2-arg form of setf. the float formatting duo 💅

Referenced by std::defaultfloat(), std::fixed(), std::hexfloat(), and std::scientific().

`const iostate std::ios_base::goodbit` — `[static]`, `[inherited]`

Indicates all is well. 🌈✨ zero problems, zero drama, the stream is thriving, she ate and left no crumbs 👑

okay we're still going, bestie — the data members keep coming and they do not stop 💜

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::time_get< _CharT, _InIter >::do_get_year(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_iostream< char_type, traits_type >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::time_get< _CharT, _InIter >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_iostream< char_type, traits_type >::operator<<(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::basic_iostream< char_type, traits_type >::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::basic_istream< _CharT, _Traits >::peek(), std::basic_ostream< _CharT, _Traits >::put(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::sync(), std::basic_istream< _CharT, _Traits >::unget(), and std::ws().

const fmtflags std::ios_base::hex [static], [inherited] — Converts integer input or generates integer output in hexadecimal base. Hex girl summer 🔥

Referenced by std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), and std::hex().

const openmode std::ios_base::in [static], [inherited] — Open for input. Default for ifstream and fstream. Come on in, the water's fine 💙

Referenced by std::basic_fstream< char >::basic_fstream(), std::basic_fstream< char >::basic_fstream(), std::basic_fstream< char >::basic_fstream(), std::basic_ifstream< char >::basic_ifstream(), std::basic_ifstream< char >::basic_ifstream(), std::basic_ifstream< char >::basic_ifstream(), std::basic_istringstream< char >::basic_istringstream(), std::basic_stringbuf< char >::basic_stringbuf(), std::basic_stringstream< char >::basic_stringstream(), std::basic_filebuf< char_type, traits_type >::_M_set_buffer(), std::basic_fstream< char >::open(), std::basic_fstream< char >::open(), std::basic_fstream< char >::open(), std::basic_ifstream< char >::open(), std::basic_ifstream< char >::open(), std::basic_ifstream< char >::open(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_filebuf< _CharT, _Traits >::pbackfail(), std::basic_streambuf< char_type, traits_type >::pubseekoff(), std::basic_streambuf< char_type, traits_type >::pubseekpos(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_streambuf< char_type, traits_type >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< char >::seekoff(), std::basic_streambuf< char_type, traits_type >::seekpos(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), std::basic_stringbuf< char >::seekpos(), std::basic_filebuf< _CharT, _Traits >::showmanyc(), std::basic_stringbuf< char >::showmanyc(), std::basic_istream< _CharT, _Traits >::tellg(), std::basic_filebuf< _CharT, _Traits >::underflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::underflow(), and std::basic_filebuf< _CharT, _Traits >::xsgetn().

const fmtflags std::ios_base::internal [static], [inherited] — Adds fill characters at a designated internal point in certain generated output, or identical to right if no such point is designated. Internal affairs 💜

Referenced by std::internal().

const fmtflags std::ios_base::left [static], [inherited] — Adds fill characters on the right (final positions) of certain generated output. (I.e., the thing you print is flush left.). Left, left, left, right, left 🎶

Referenced by std::num_put< _CharT, _OutIter >::do_put(), std::left(), and std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator<<.

const fmtflags std::ios_base::oct [static], [inherited] — Converts integer input or generates integer output in octal base. Oct-oct-oct 🐙

Referenced by std::oct().

const openmode std::ios_base::out [static], [inherited] — Open for output. Default for ofstream and fstream. Out and about 💚

Referenced by std::basic_fstream< char >::basic_fstream(), std::basic_fstream< char >::basic_fstream(), std::basic_fstream< char >::basic_fstream(), std::basic_ofstream< char >::basic_ofstream(), std::basic_ofstream< char >::basic_ofstream(), std::basic_ofstream< char >::basic_ofstream(), std::basic_ostringstream< char >::basic_ostringstream(), std::basic_stringbuf< char >::basic_stringbuf(), std::basic_stringstream< char >::basic_stringstream(), std::basic_filebuf< char_type, traits_type >::_M_set_buffer(), std::basic_fstream< char >::open(), std::basic_fstream< char >::open(), std::basic_fstream< char >::open(), std::basic_ofstream< char >::open(), std::basic_ofstream< char >::open(), std::basic_ofstream< char >::open(), std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::pbackfail(), std::basic_streambuf< char_type, traits_type >::pubseekoff(), std::basic_streambuf< char_type, traits_type >::pubseekpos(), std::basic_streambuf< char_type, traits_type >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< char >::seekoff(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_streambuf< char_type, traits_type >::seekpos(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), std::basic_stringbuf< char >::seekpos(), std::basic_ostream< _CharT, _Traits >::tellp(), and std::basic_filebuf< _CharT, _Traits >::xsputn().

const fmtflags std::ios_base::right [static], [inherited] — Adds fill characters on the left (initial positions) of certain generated output. (I.e., the thing you print is flush right.). Right on 💖

Referenced by std::right().

const fmtflags std::ios_base::scientific [static], [inherited] — Generates floating-point output in scientific notation. Science slay 🧪

Referenced by std::hexfloat(), and std::scientific().

const fmtflags std::ios_base::showbase [static], [inherited] — Generates a prefix indicating the numeric base of generated integer output. Show it off 💅

Referenced by std::num_put< _CharT, _OutIter >::do_put(), std::noshowbase(), and std::showbase().

const fmtflags std::ios_base::showpoint [static], [inherited] — Generates a decimal-point character unconditionally in generated floating-point output. Point made ✨

Referenced by std::noshowpoint(), and std::showpoint().

const fmtflags std::ios_base::showpos [static], [inherited] — Generates a + sign in non-negative generated numeric output. Positivity only ☀️

Referenced by std::noshowpos(), and std::showpos().

const fmtflags std::ios_base::skipws [static], [inherited] — Skips leading white space before certain input operations. Space? Don't know her 🚫

Referenced by std::noskipws(), std::__detail::operator>>(), std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator>>, and std::skipws().

const openmode std::ios_base::trunc [static], [inherited] — Truncate an existing stream when opening. Default for ofstream. Cut it off ✂️
const fmtflags std::ios_base::unitbuf [static], [inherited] — Flushes output after each output operation. Flush it out 💧

Referenced by std::basic_ostream< _CharT, _Traits >::sentry::~sentry(), std::nounitbuf(), and std::unitbuf().

const fmtflags std::ios_base::uppercase [static], [inherited] — Replaces certain lowercase letters with their uppercase equivalents in generated output. LOUDER 📢

Referenced by std::num_put< _CharT, _OutIter >::do_put(), std::nouppercase(), and std::uppercase().

Author 💖

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STD::BASIC_ISTREAM(3)

🌸 std::basic_istream< _CharT, _Traits >(3) 🌸 — Library Functions Manual

✨ NAME ✨

🦋 SYNOPSIS 🦋

🎀 Classes

🌈 Public Types

💜 Public Member Functions

🔥 Extractors

🌸 Unformatted Input Functions

👑 Static Public Member Functions

✨ Static Public Attributes ✨

🎀 Protected Types 🎀

🦋 Protected Member Functions 🦋

💜 Protected Attributes 💜

🌈 Friends 🌈

⭐ Detailed Description ⭐

🍓 Template Parameters 🍓

✨ Member Typedef Documentation ✨

🌸 Member Enumeration Documentation 🌸

💫 Constructor & Destructor Documentation 💫

🔥 Member Function Documentation 🔥

copyfmt — the glow-up montage 💅

eof — vibe check, but for end-of-file 🌸

exceptions (the const one) — mask reveal 👑

exceptions (the setter one) — now you're setting the mask 💀

fail — another fast error check, we love consistency ✨

fill (getter) — the empty character, she's so iconic 🎀

fill (setter) — new character just dropped 🦋

flags (getter) — format flags, come get y'all 🧚

flags (setter) — swap the whole vibe in one go 💅

gcount — how many characters did we just eat? 🍓

get — simple extraction 🎀

get — extraction into another streambuf 🦋

get — extraction into another streambuf, with a stop character 🌸

get — simple extraction, single character 🎀

get — multiple characters, go off 👑

get — multiple characters with a stop character 🌈

getline — string extraction, the moment we've all been waiting for ✨

getline — the char specialization 🌟

getline — the template one, back at it again 🫶

locale std::ios_base::getloc () const [inline], [nodiscard], [inherited]

template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT, _Traits >::good () const [inline], [nodiscard], [inherited]

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (void )

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (streamsize __n)

template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::ignore (streamsize __n, char __delim) [inline]

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (streamsize __n, int_type __delim)

template<typename _CharT, typename _Traits> locale std::basic_ios< _CharT, _Traits >::imbue (const locale & __loc) [inherited]

template<typename _CharT, typename _Traits> void std::basic_ios< _CharT, _Traits >::init (basic_streambuf< _CharT, _Traits > * __sb) [protected], [inherited]

long & std::ios_base::iword (int __ix) [inline], [inherited]

template<typename _CharT, typename _Traits> char std::basic_ios< _CharT, _Traits >::narrow (char_type __c, char __dfault) const [inline], [inherited]

template<typename _CharT, typename _Traits> std::basic_ios< _CharT, _Traits >::operator bool () const [inline], [explicit], [nodiscard], [inherited]

template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT, _Traits >::operator! () const [inline], [nodiscard], [inherited]

template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (__ios_type &(* __pf )(__ios_type &)) [inline]

template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (__istream_type &(* __pf )(__istream_type &)) [inline]

template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::operator>> (__streambuf_type * __sb)

template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (bool & __n) [inline]

template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (double & __f) [inline]

template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (float & __f) [inline]

🌟 operator>> (int) — integer arithmetic extractor

🎀 operator>> (manipulators) — ios_base &(*__pf)(ios_base &) — [inline]

🦋 operator>> (long) — [inline]

🍓 operator>> (long double) — [inline]

💜 operator>> (long long) — [inline]

🌈 operator>> (short)

💖 operator>> (unsigned int) — [inline]

🎀 operator>> (unsigned long) — [inline]

🦋 operator>> (unsigned long long) — [inline]

💅 operator>> (unsigned short) — [inline]

👑 operator>> (void*) — [inline]

🔥 peek — looking ahead in the stream

🌸 std::ios_base::precision() — [inline], [nodiscard], [inherited]

🧚 std::ios_base::precision(streamsize __prec) — [inline], [inherited]

🎀 putback — unextracting a single character

🦋 std::ios_base::pword(int __ix) — [inline], [inherited]

💜 std::basic_ios< _CharT, _Traits >::rdbuf() const — [inline], [nodiscard], [inherited]

🎀 std::basic_ios< _CharT, _Traits >::rdbuf(basic_streambuf< _CharT, _Traits > * __sb) — [inherited]

🧚 std::basic_ios< _CharT, _Traits >::rdstate() const — [inline], [nodiscard], [inherited]

🌈 read — extraction without delimiters

streamsize std::basic_istream<_CharT, _Traits>::readsome(char_type * __s, streamsize __n)

void std::ios_base::register_callback(event_callback __fn, int __index)

🌸 `std::basic_istream< _CharT, _Traits >(3)` 🌸 — Library Functions Manual

`copyfmt` — the glow-up montage 💅

`eof` — vibe check, but for end-of-file 🌸

`exceptions` (the const one) — mask reveal 👑

`exceptions` (the setter one) — now you're setting the mask 💀

`fail` — another fast error check, we love consistency ✨

`fill` (getter) — the empty character, she's so iconic 🎀

`fill` (setter) — new character just dropped 🦋

`flags` (getter) — format flags, come get y'all 🧚

`flags` (setter) — swap the whole vibe in one go 💅

`gcount` — how many characters did we just eat? 🍓

`get` — simple extraction 🎀

`get` — extraction into another streambuf 🦋

`get` — extraction into another streambuf, with a stop character 🌸

`get` — simple extraction, single character 🎀

`get` — multiple characters, go off 👑

`get` — multiple characters with a stop character 🌈

`getline` — string extraction, the moment we've all been waiting for ✨

`getline` — the `char` specialization 🌟

`getline` — the template one, back at it again 🫶

`locale std::ios_base::getloc () const` `[inline]`, `[nodiscard]`, `[inherited]`

`template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT, _Traits >::good () const` `[inline]`, `[nodiscard]`, `[inherited]`

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (void )`

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (streamsize __n)`

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::ignore (streamsize n, char delim)` `[inline]`

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::ignore (streamsize __n, int_type __delim)`

`template<typename _CharT, typename _Traits> locale std::basic_ios< _CharT, _Traits >::imbue (const locale & __loc)` `[inherited]`

`template<typename _CharT, typename _Traits> void std::basic_ios< _CharT, _Traits >::init (basic_streambuf< _CharT, _Traits > * __sb)` `[protected]`, `[inherited]`

`long & std::ios_base::iword (int __ix)` `[inline]`, `[inherited]`

`template<typename _CharT, typename _Traits> char std::basic_ios< _CharT, _Traits >::narrow (char_type c, char dfault) const` `[inline]`, `[inherited]`

`template<typename _CharT, typename _Traits> std::basic_ios< _CharT, _Traits >::operator bool () const` `[inline]`, `[explicit]`, `[nodiscard]`, `[inherited]`

`template<typename _CharT, typename _Traits> bool std::basic_ios< _CharT, _Traits >::operator! () const` `[inline]`, `[nodiscard]`, `[inherited]`

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (__ios_type &(* pf )(ios_type &))` `[inline]`

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (__istream_type &(* pf )(istream_type &))` `[inline]`

`template<typename _CharT, typename _Traits> basic_istream< _CharT, _Traits > & std::basic_istream< _CharT, _Traits >::operator>> (__streambuf_type * __sb)`

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (bool & __n)` `[inline]`

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (double & __f)` `[inline]`

`template<typename _CharT, typename _Traits> __istream_type & std::basic_istream< _CharT, _Traits >::operator>> (float & __f)` `[inline]`

🌟 `operator>>` (int) — integer arithmetic extractor

🎀 `operator>>` (manipulators) — `ios_base &(__pf)(ios_base &)` — [inline]*

🦋 `operator>>` (long) — [inline]

🍓 `operator>>` (long double) — [inline]

💜 `operator>>` (long long) — [inline]

🌈 `operator>>` (short)

💖 `operator>>` (unsigned int) — [inline]

🎀 `operator>>` (unsigned long) — [inline]

🦋 `operator>>` (unsigned long long) — [inline]

💅 `operator>>` (unsigned short) — [inline]

👑 `operator>>` (void) — [inline]*

🔥 `peek` — looking ahead in the stream

🌸 `std::ios_base::precision()` — [inline], [nodiscard], [inherited]

🧚 `std::ios_base::precision(streamsize __prec)` — [inline], [inherited]

🎀 `putback` — unextracting a single character

🦋 `std::ios_base::pword(int __ix)` — [inline], [inherited]

💜 `std::basic_ios< _CharT, _Traits >::rdbuf() const` — [inline], [nodiscard], [inherited]

🎀 `std::basic_ios< _CharT, _Traits >::rdbuf(basic_streambuf< _CharT, _Traits > * __sb)` — [inherited]

🧚 `std::basic_ios< _CharT, _Traits >::rdstate() const` — [inline], [nodiscard], [inherited]

🌈 `read` — extraction without delimiters

`streamsize std::basic_istream<_CharT, _Traits>::readsome(char_type * s, streamsize n)`

`void std::ios_base::register_callback(event_callback fn, int index)`

`basic_istream< _CharT, _Traits > & std::basic_istream<_CharT, _Traits>::seekg(off_type __off, ios_base::seekdir __dir)`

`basic_istream< _CharT, _Traits > & std::basic_istream<_CharT, _Traits>::seekg(pos_type __pos)`

`fmtflags std::ios_base::setf(fmtflags __fmtfl)`

`fmtflags std::ios_base::setf(fmtflags fmtfl, fmtflags mask)`

`void std::basic_ios<_CharT, _Traits>::setstate(iostate __state)`

`int std::basic_istream<_CharT, _Traits>::sync(void)`

`bool std::ios_base::sync_with_stdio(bool __sync = true)`

`basic_istream< _CharT, _Traits >::pos_type std::basic_istream<_CharT, _Traits>::tellg(void)`

`basic_ostream< _CharT, _Traits > * std::basic_ios<_CharT, _Traits>::tie() const`

`basic_ostream< _CharT, _Traits > * std::basic_ios<_CharT, _Traits>::tie(basic_ostream< _CharT, _Traits > * __tiestr)`

`basic_istream< _CharT, _Traits > & std::basic_istream<_CharT, _Traits>::unget(void)`

`void std::ios_base::unsetf(fmtflags __mask)`

`char_type std::basic_ios<_CharT, _Traits>::widen(char __c) const`

`streamsize std::ios_base::width () const` — `[inline]`, `[nodiscard]`, `[inherited]`

`streamsize std::ios_base::width (streamsize __wide)` — `[inline]`, `[inherited]`

`int std::ios_base::xalloc ()` — `[static]`, `[inherited]`

`template<typename _CharT, typename _Traits> streamsize std::basic_istream< _CharT, _Traits >::_M_gcount` — `[protected]`

`const fmtflags std::ios_base::adjustfield` — `[static]`, `[inherited]`

`const openmode std::ios_base::app` — `[static]`, `[inherited]`

`const openmode std::ios_base::ate` — `[static]`, `[inherited]`