STD::BASIC_OSTREAM(3)

📦
version 16.2.1+r23+gd564253eb6c8 · 15 versions
, in arch rolling, fedora 44

💖 std::basic_ostream< _CharT, _Traits > — Library Functions Manual 💖

✨ NAME ✨

std::basic_ostream< _CharT, _Traits > — Template class basic_ostream.

okay bestie, she’s the output-stream template and she is iconic. No cap. 💅

🌸 SYNOPSIS 🌸

#include <ostream>

Inherits std::basic_ios< _CharT, _Traits >.

Inherited by std::basic_iostream< char >, std::basic_iostream< wchar_t >, std::basic_ofstream< char >, std::basic_ofstream< wchar_t >, std::basic_ostringstream< char >, std::basic_ostringstream< wchar_t >, std::basic_iostream< _CharT, _Traits >, std::basic_ofstream< _CharT, _Traits >, and std::basic_ostringstream< _CharT, _Traits, _Alloc >.

🎀 Classes 🎀

  • class sentry — Performs setup work for output streams. She does the pre-game setup before the output stream does its thing. 🫶

💖 Public Types 💖

  • typedef ctype< _CharT > __ctype_type
  • typedef basic_ios< _CharT, _Traits > __ios_type
  • typedef num_put< _CharT, ostreambuf_iterator< _CharT, _Traits > > __num_put_type
  • typedef basic_ostream< _CharT, _Traits > __ostream_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.
  • typedef void(* event_callback) (event __e, ios_base &__b, int __i) — The type of an event callback function.
  • typedef _Ios_Fmtflags fmtflags — This is a bitmask type.
  • typedef _Traits::int_type int_type
  • typedef _Ios_Iostate iostate — This is a bitmask type.
  • typedef _Traits::off_type off_type
  • typedef _Ios_Openmode openmode — This is a bitmask type.
  • typedef _Traits::pos_type pos_type
  • typedef _Ios_Seekdir seekdir — This is an enumerated type.
  • typedef _Traits traits_type
  • typedef num_get< _CharT, istreambuf_iterator< _CharT, _Traits > > __num_get_type

🔥 Public Member Functions 🔥

  • basic_ostream (__streambuf_type *__sb) — Base constructor.
  • virtual ~basic_ostream () — Base destructor.
  • const locale & _M_getloc () const — Locale access.
  • template<typename _ValueT> basic_ostream< _CharT, _Traits > & _M_insert (_ValueT __v)
  • void _M_setstate (iostate __state)
  • bool bad () const — Fast error checking.
  • void clear (iostate __state=goodbit) — [R]sets the error state.
  • basic_ios & copyfmt (const basic_ios &__rhs) — Copies fields of __rhs into this.
  • 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.
  • 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.
  • __ostream_type & flush () — Synchronizing the stream buffer.
  • locale getloc () const — Locale access.
  • bool good () const — Fast error checking.
  • locale imbue (const locale &__loc) — Moves to a new locale.
  • long & iword (int __ix) — Access to integer array.
  • char narrow (char_type __c, char __dfault) const — Squeezes characters.
  • __ostream_type & operator<< (__streambuf_type *__sb) — Extracting from another streambuf.
  • __ostream_type & operator<< (const void *__p) — Pointer arithmetic inserters.
  • __ostream_type & operator<< (const volatile void *__p)
  • __ostream_type & operator<< (nullptr_t)
  • 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.
  • __ostream_type & seekp (off_type, ios_base::seekdir) — Changing the current write position.
  • __ostream_type & seekp (pos_type) — Changing the current write position.
  • 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.
  • pos_type tellp () — Getting the current write position.
  • 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.
  • 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.
  • __ostream_type & operator<< (__ostream_type &(*__pf)(__ostream_type &)) — Interface for manipulators.
  • __ostream_type & operator<< (__ios_type &(*__pf)(__ios_type &)) — Interface for manipulators.
  • __ostream_type & operator<< (ios_base &(*__pf)(ios_base &)) — Interface for manipulators.

✨ Inserters ✨

All the operator<< functions (aka formatted output functions) have some common behavior. Each starts by constructing a temporary object of type std::basic_ostream::sentry. This can have several effects, concluding with the setting of a status flag; see the sentry documentation for more.

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

If an exception is thrown during insertion, ios_base::badbit will be turned on in the stream's error state without causing an ios_base::failure to be thrown. The original exception will then be rethrown.

bestie, read that again: badbit gets turned on, no ios_base::failure gets thrown, and then the original exception is rethrown. That's the rule. 💀
  • __ostream_type & operator<< (long __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (unsigned long __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (bool __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (short __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (unsigned short __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (int __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (unsigned int __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (long long __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (unsigned long long __n) — Integer arithmetic inserters.
  • __ostream_type & operator<< (double __f) — Floating point arithmetic inserters.
  • __ostream_type & operator<< (float __f) — Floating point arithmetic inserters.
  • __ostream_type & operator<< (long double __f) — Floating point arithmetic inserters.

💅 Unformatted Output Functions 💅

All the unformatted output functions have some common behavior. Each starts by constructing a temporary object of type std::basic_ostream::sentry. This has several effects, concluding with the setting of a status flag; see the sentry documentation for more.

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

If an exception is thrown during insertion, ios_base::badbit will be turned on in the stream's error state. If badbit is on in the stream's exceptions mask, the exception will be rethrown without completing its actions.

  • __ostream_type & put (char_type __c) — Simple insertion.
  • __ostream_type & write (const char_type *__s, streamsize __n) — Character string insertion.
  • 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 ✨

okay bestie, gather round. these are the static constants that live on the class. no cap, they're iconic. 💅

  • static const openmode __noreplace — there's literally no description for this one, she just exists. 🫶
  • static const fmtflags adjustfield — a mask of left|right|internal. lowkey useful for the 2-arg form of setf. 💅
  • static const openmode app — seek to end before each write. periodt.
  • static const openmode ate — open and seek to end immediately after opening. no cap.
  • static const iostate badbit — indicates a loss of integrity in an input or output sequence (such as an irrecoverable read error from a file). it's giving "something went wrong" energy. 😭
  • static const fmtflags basefield — a mask of dec|oct|hex. useful for the 2-arg form of setf.
  • static const seekdir beg — request a seek relative to the beginning of the stream. classic.
  • static const openmode binary — perform input and output in binary mode (as opposed to text mode). ngl this is probably not what you think it is; see https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary. bestie read that link. 🦋
  • static const fmtflags boolalpha — insert/extract bool in alphabetic rather than numeric format. slay.
  • static const seekdir cur — request a seek relative to the current position within the sequence.
  • 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. bye.
  • 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. not the vibe.
  • static const fmtflags fixed — generate floating-point output in fixed-point notation.
  • static const fmtflags floatfield — a mask of scientific|fixed. useful for the 2-arg form of setf.
  • static const iostate goodbit — indicates all is well. we love to see it. 💖
  • static const fmtflags hex — converts integer input or generates integer output in hexadecimal base.
  • static const openmode in — open for input. 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.). flush left queen. 👑
  • static const fmtflags oct — converts integer input or generates integer output in octal base.
  • static const openmode out — open for output. 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.). flush right queen. 👑
  • static const fmtflags scientific — generates floating-point output in scientific notation.
  • 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.
  • 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. default for ofstream.
  • static const fmtflags unitbuf — flushes output after each output operation. flush after every op, she's thorough.
  • static const fmtflags uppercase — replaces certain lowercase letters with their uppercase equivalents in generated output.

🛡️ Protected Types 🛡️

  • enum { _S_local_word_size } — that's the whole vibe. no extra tea. 🦋

🫶 Protected Member Functions 🫶

  • basic_ostream(basic_iostream<_CharT, _Traits>&)
  • basic_ostream(basic_ostream&& __rhs)
  • basic_ostream(const basic_ostream&) = delete
  • void _M_cache_locale(const locale& __loc)
  • void _M_call_callbacks(event __ev) throw()
  • void _M_dispose_callbacks(void) throw()
  • _Words& _M_grow_words(int __index, bool __iword)
  • void _M_init() throw()
  • template<typename _ValueT> __ostream_type& _M_insert(_ValueT __v)
  • 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. ✨
  • void move(basic_ios&& __rhs)
  • void move(basic_ios& __rhs)
  • basic_ostream& operator=(basic_ostream&& __rhs)
  • basic_ostream& operator=(const basic_ostream&) = delete
  • void set_rdbuf(basic_streambuf<_CharT, _Traits>* __sb)
  • void swap(basic_ios& __rhs) noexcept
  • void swap(basic_ostream& __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
  • 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 — the sentry is a friend, periodt.

🌈 Detailed Description 🌈

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

Template class basic_ostream.

Template Parameters

  • _CharT — Type of character stream.
  • _Traits — Traits for character type, defaults to char_traits<_CharT>.

This is the base class for all output streams. It provides text formatting of all builtin types, and communicates with any class derived from basic_streambuf to do the actual output. main character energy, fr fr. 👑

📚 Member Typedef Documentation 📚

__num_get_type

template<typename _CharT, typename _Traits> typedef num_get<_CharT, istreambuf_iterator<_CharT, _Traits> > std::basic_ios< _CharT, _Traits >::__num_get_type [inherited]

These are non-standard types. 💅

event_callback

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

The type of an event callback function.

Parameters:

  • __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().

fmtflags

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

iostate

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

openmode

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

seekdir

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().

🎀 Constructor & Destructor Documentation 🎀

basic_ostream(__streambuf_type* __sb)

template<typename _CharT, typename _Traits>
std::basic_ostream< _CharT, _Traits >::basic_ostream (__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_ostream< _CharT, _Traits >::sentry::sentry(), and operator<<().

~basic_ostream()

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

Base destructor. This does very little apart from providing a virtual base dtor.

💅 Member Function Documentation 💅

_M_getloc()

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

Locale access.

Returns:

  • A reference to the current locale.

Like getloc above, but returns a reference instead of generating a copy.

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().

bad()

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

Fast error checking.

Returns:

  • True if the badbit is set.

Note that other iostate flags may also be set.

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

clear()

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

[Re]sets the error state.

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.

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

...the full squad that references it, bestie, and yes every single one of them:

  • 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()

(Yes, some of these show up twice in the original list. That's just how it is. We don't question the list. We respect the list. 💅)

🪞 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 glow-up-by-cloning, honestly.

Parameters

  • __rhs — the source values for the copies.

Returns

  • Reference to this object.

Okay so the tea: all fields of __rhs get copied into this object, except that rdbuf() and rdstate() stay exactly how they were. All the values sitting in the pword and iword arrays? Copied. Before the copying even happens, each callback gets invoked with erase_event. After the copying, each (new) callback gets invoked with copyfmt_event. And then the final step, the little bow on top, is copying 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().

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

Fast error checking. Speed-run status check, basically.

Returns

  • True if the eofbit is set.
Heads up bestie: other iostate flags may also be set. Don't assume it's only eof. 👀

💥 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 one changes nothing in the stream, it's purely a peek. Wanna know what the return value actually means? Go read the one-argument version, exceptions(iostate). It's all there.

Referenced by clear(), and copyfmt().

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

Throwing exceptions on errors. The sequel. The one with the plot twist.

Parameters

  • __except — the new exceptions mask.

So by default, error flags just get set silently, no drama, no announcement. But you can set an exceptions mask for each stream. And if a bit in the mask becomes set in the error flags? Boom — an exception of type std::ios_base::failure gets thrown.

And here's the part that catches people: if the error flag is already set when you add the exceptions mask, the exception is thrown immediately. Like, right then. No waiting. 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);
}

🩺 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.

Checking the badbit inside fail() is historical practice — that's just the lore, okay? 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().

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

Retrieves the empty character. The lil filler character. The one who pads out your formatting.

Returns

  • The current fill character.

It defaults to a space (' ') in the current locale.

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

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

Sets a new empty character. Pick your own padding, diva.

Parameters

  • __ch — the new character.

Returns

  • The previous fill character.

So the fill character is what gets used to fill out space when P+ characters have been requested (like, say, via setw), Q characters are actually used, and Q<P. It defaults to a space (' ') in the current locale.

🚩 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>>.

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

Setting new format flags all at once. One shot, whole new personality.

Parameters

  • __fmtfl — the new flags to set.

Returns

  • The previous format control flags.

This function overwrites all the format flags with __fmtfl. Not a merge, bestie. A full replacement. The old flags are gone-gone.

🚰 template<typename _CharT, typename _Traits> basic_ostream< _CharT, _Traits > & std::basic_ostream< _CharT, _Traits >::flush ()

Synchronizing the stream buffer.

Returns

  • *this

If rdbuf() is a null pointer, it changes nothing. Otherwise it calls rdbuf()->pubsync(), and if that returns -1, it sets badbit. Simple as.

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

Referenced by std::flush().

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

Locale access.

Returns

  • A copy of the current locale.

Here's how it decides: if imbue(loc) has previously been called, then this function returns loc. Otherwise, it returns a copy of std::locale(), the global C++ locale.

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 a wrapper around rdstate. Nothing more, nothing less.

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

Moves to a new locale. Glow-up, but make it internationalization.

Parameters

  • __loc — the new locale.

Returns

  • The previous locale.

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

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. Periodt.

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_ios< char_type, traits_type >::basic_ios(), std::basic_istream< char_type, traits_type >::basic_istream(), std::basic_istringstream< char >::basic_istringstream(), std::basic_istringstream< char >::basic_istringstream(), std::basic_istringstream< char >::basic_istringstream(), std::basic_ofstream< char >::basic_ofstream(), std::basic_ofstream< char >::basic_ofstream(), std::basic_ofstream< char >::basic_ofstream(), std::basic_ostream< char_type, traits_type >::basic_ostream(), std::basic_ostringstream< char >::basic_ostringstream(), std::basic_ostringstream< char >::basic_ostringstream(), std::basic_ostringstream< char >::basic_ostringstream(), std::basic_stringstream< char >::basic_stringstream(), std::basic_stringstream< char >::basic_stringstream(), and std::basic_stringstream< char >::basic_stringstream().

🔢 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.

So 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. Fr fr, don't be out here storing that reference like it's gonna last forever. It will not.

References iword().

Referenced by iword().

(Yes. It references itself and is referenced by itself. Main character energy. 👑)

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

Squeezes characters. Compression, but for 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) ...

💅 operator! — the quick-and-easy status check

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

okay so this is the quick-and-easy status check ✨. It lets you write constructs such as if (!a_stream) ... and while (a_stream) ... — super handy for vibe checks, no cap. 🫶

✨ operator<< — manipulator interface (ios_type)

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

This is the interface for manipulators 💜. Manipulators such as std::endl and std::hex use these functions in constructs like "std::cout << std::endl". For more information, see the iomanip header 👀.

🦋 operator<< — manipulator interface (ostream_type)

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

Same vibe, bestie: interface for manipulators 🦋. Manipulators such as std::endl and std::hex use these functions in constructs like "std::cout << std::endl". For more information, see the iomanip header.

💖 operator<< — extracting from another streambuf

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

Extracting from 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 __sb and inserted into *this until one of the following occurs:

  • the input stream reaches end-of-file,
  • insertion into the output sequence fails (in this case, the character that would have been inserted is not extracted), or
  • an exception occurs while getting a character from __sb, which sets failbit in the error state

If the function inserts no characters, failbit is set.

🔢 operator<< — integer arithmetic inserters (bool)

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

Integer arithmetic inserters 🔢

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 perform numeric formatting.

📍 operator<< — pointer arithmetic inserters

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (const void * __p)
       [inline]

Pointer arithmetic inserters 📍

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 perform numeric formatting.

🧮 operator<< — floating point arithmetic inserters (double)

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

Floating point arithmetic inserters 🧮

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 perform numeric formatting.

🌸 operator<< — floating point arithmetic inserters (float)

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

Floating point arithmetic inserters 🌸

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 perform numeric formatting.

🔥 operator<< — integer arithmetic inserters (int)

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

Integer arithmetic inserters 🔥

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 perform numeric formatting.

🎀 operator<< — manipulator interface (ios_base)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (ios_base &(* __pf
       )(ios_base &)) [inline]

Interface for manipulators 🎀. Manipulators such as std::endl and std::hex use these functions in constructs like "std::cout << std::endl". For more information, see the iomanip header.

💜 operator<< — integer arithmetic inserters (long)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (long __n) [inline]

Integer arithmetic inserters 💜

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 perform numeric formatting.

🌈 operator<< — floating point arithmetic inserters (long double)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (long double __f)
       [inline]

Floating point arithmetic inserters 🌈

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 perform numeric formatting.

⭐ operator<< — integer arithmetic inserters (long long)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (long long __n)
       [inline]

Integer arithmetic inserters ⭐

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 perform numeric formatting.

🍓 operator<< — integer arithmetic inserters (short)

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

Integer arithmetic inserters 🍓

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 perform numeric formatting.

References:

basic_ostream(), std::ios_base::badbit, std::ostreambuf_iterator< _CharT, _Traits >::failed(), std::ios_base::goodbit, std::num_put< _CharT, _OutIter >::put(), std::basic_ios< _CharT, _Traits >::setstate(), and std::use_facet().

🧚 operator<< — integer arithmetic inserters (unsigned int)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (unsigned int __n)
       [inline]

Integer arithmetic inserters 🧚

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 perform numeric formatting.

💫 operator<< — integer arithmetic inserters (unsigned long)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (unsigned long __n)
       [inline]

Integer arithmetic inserters 💫

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 perform numeric formatting.

🫶 operator<< — integer arithmetic inserters (unsigned long long)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (unsigned long long
       __n) [inline]

Integer arithmetic inserters 🫶

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 perform numeric formatting.

🎀 operator<< — integer arithmetic inserters (unsigned short)

   template<typename _CharT, typename _Traits> __ostream_type &
       std::basic_ostream< _CharT, _Traits >::operator<< (unsigned short __n)
       [inline]

Integer arithmetic inserters 🎀

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 perform numeric formatting.

🚩 precision — get the precision

   streamsize std::ios_base::precision () const [inline],  [nodiscard],
       [inherited]

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.

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

🎛️ precision — set the precision

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

Changing flags 🎛️

Parameters

  • __prec — The new precision value.

Returns

  • The previous value of precision().

✍️ put — simple insertion

   template<typename _CharT, typename _Traits> basic_ostream< _CharT, _Traits >
       & std::basic_ostream< _CharT, _Traits >::put (char_type __c)

Simple insertion ✍️

Parameters

  • __c — The character to insert.

Returns

  • *this

Tries to insert __c.

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

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

Referenced by std::endl(), and std::ends().

🗂️ pword — access to void pointer array

   void *& std::ios_base::pword (int __ix) [inline],  [inherited]

Access to void pointer array 🗂️

Parameters

  • __ix — Index into the array.

Returns

  • A reference to a void* associated with the index.

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. 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.

🌊 rdbuf — accessing the underlying buffer

   template<typename _CharT, typename _Traits> basic_streambuf< _CharT, _Traits
       > * std::basic_ios< _CharT, _Traits >::rdbuf () const [inline],
       [nodiscard],  [inherited]

Accessing the underlying buffer 🌊

Returns

  • The current stream buffer.

This does not change the state of the stream.

Referenced by the whole squad:

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::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().

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

okay bestie, this one is literally called Changing the underlying buffer. 💅

Parameters

  • __sb — the brand new stream buffer, slay.

Returns

  • the previous stream buffer. yes queen, we hand it back to you.

So what it does: it associates a new buffer with the current stream, and (bonus!) clears the error state. ✨

⚠️ girlypop, listen up, because this is the messy part. 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().

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

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 — that's where all the actual bits live. Most users will just 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().

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.

Registers a function as an event callback, with an integer parameter that gets passed to the function when it's invoked. Multiple copies of the function are allowed. And if there are multiple callbacks? They are invoked in the order they were registered — first come, first served, no cutting the line. 🫶

template<typename _CharT, typename _Traits> basic_ostream< _CharT, _Traits > & std::basic_ostream< _CharT, _Traits >::seekp (off_type __off, ios_base::seekdir __dir)

Changing the current write 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). If that function fails, it sets failbit. 🙈

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

template<typename _CharT, typename _Traits> basic_ostream< _CharT, _Traits > & std::basic_ostream< _CharT, _Traits >::seekp (pos_type __pos)

Changing the current write position. 🦋 (the pos_type version, bestie)

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. 🙈

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

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 function sets additional flags in format control. Flags that were previously set remain set — nothing gets wiped, we're just adding. 💖

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

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

Setting new format flags. ⭐ (the two-argument glow-up)

Parameters

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

Returns

  • the previous format control flags.

This function clears mask in the format flags, then sets fmtfl & mask. An example mask is ios_base::adjustfield. 🎯

template<typename _CharT, typename _Traits> 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(), and std::ws().

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.
bestie, read this carefully: 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

template<typename _CharT, typename _Traits> basic_ostream< _CharT, _Traits >::pos_type std::basic_ostream< _CharT, _Traits >::tellp ()

Getting the current write 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,out).

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

template<typename _CharT, typename _Traits> 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.

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

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

template<typename _CharT, typename _Traits> 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.

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. bye girl, you're un-set. 💅

template<typename _CharT, typename _Traits> 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.

Maps a character of char to a character of char_type.

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

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]

Flags access. 📏

Returns

  • the minimum field width to generate on output operations.

Minimum field width refers to the number of characters.

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]

Changing flags. ✏️

Parameters

  • __wide — the new width value.

Returns

  • the previous value of width().

template<typename _CharT, typename _Traits> basic_ostream< _CharT, _Traits > & std::basic_ostream< _CharT, _Traits >::write (const char_type * __s, streamsize __n)

Character string insertion. ✍️

Parameters

  • __s — the array to insert.
  • __n — maximum number of characters to insert.

Returns

  • *this

Characters are copied from __s and inserted into the stream until one of the following happens:

  • __n characters are inserted
  • inserting into the output sequence fails (in this case, badbit will be set in the stream's error state) 💀
Note: this function is not overloaded on signed char and unsigned char. don't come for it, it's just built like that. 🙈

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

Access to unique indices. 🔢

Returns

  • an integer different from all previous calls.

This function returns a unique integer every single 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. xalloc is guaranteed to return an index that is safe to use in the iword and pword arrays. periodt. 💅

✨ Member Data Documentation ✨

  • const fmtflags std::ios_base::adjustfield [static], [inherited] — It's a mask made of left|right|internal. Super useful for the 2-arg form of setf, fr fr.

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 the end before each write. It's giving "always append" realness.

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 the end immediately after opening. Lowkey the "jump to the end" vibe.

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 (like an irrecoverable read error from a file). This is the "something went terribly wrong" flag, bestie. Not cute.

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_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. Perfect for the 2-arg form of setf, iykyk.

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. It's giving "start from the top" energy.

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

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 true/false instead of 1/0, bestie.

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. Main character energy: you stay where you are, just offset.

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. Base 10, the classic.

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. It's giving "from the bottom" vibes.

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. Not me hitting EOF and feeling empty 😭

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. Basically "the vibe was off" flag. 💀

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 scientific notation here, just straight-up decimals.

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, periodt.

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

  • const iostate std::ios_base::goodbit [static], [inherited] — Indicates all is well. It's giving "no thoughts, just vibes" but for streams. ✨

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. Base 16, for when you're feeling extra.

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, bestie.

okay so that last constant's referenced-by list was still going, and here's the whole rest of it — every single entry, no skips, no cap:

  • 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()
  • std::basic_filebuf< _CharT, _Traits >::xsgetn()
  • const fmtflags std::ios_base::internal [static], [inherited] — drops the fill characters at a point inside the output that you specifically designate… and if you never designate one, bestie, it behaves exactly like right. Referenced by:
    • std::internal()
  • const fmtflags std::ios_base::left [static], [inherited] — pads with fill characters on the right (the final positions) of certain generated output. I.e. the thing you print is flush left. Referenced by:
    • std::num_put< _CharT, _OutIter >::do_put()
    • std::left()
    • 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 (that's base 8, queen). Referenced by:
    • std::oct()
  • const openmode std::ios_base::out [static], [inherited] — open for output. this one's the default for ofstream and fstream, so she's kinda the main character. 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()
    • std::basic_filebuf< _CharT, _Traits >::xsputn()
  • const fmtflags std::ios_base::right [static], [inherited] — pads with fill characters on the left (the initial positions) of certain generated output. I.e. the thing you print is flush right. Referenced by:
    • std::right()
  • const fmtflags std::ios_base::scientific [static], [inherited] — generates floating-point output in scientific notation. very science-core of her 🧪 Referenced by:
    • std::hexfloat()
    • std::scientific()
  • const fmtflags std::ios_base::showbase [static], [inherited] — generates a prefix that tells you the numeric base of generated integer output. Referenced by:
    • std::num_put< _CharT, _OutIter >::do_put()
    • std::noshowbase()
    • std::showbase()
  • const fmtflags std::ios_base::showpoint [static], [inherited] — generates a decimal-point character unconditionally in floating-point output. she said you're getting the point, periodt. Referenced by:
    • std::noshowpoint()
    • std::showpoint()
  • const fmtflags std::ios_base::showpos [static], [inherited] — generates a + sign in non-negative generated numeric output. Referenced by:
    • std::noshowpos()
    • std::showpos()
  • const fmtflags std::ios_base::skipws [static], [inherited] — skips leading white space before certain input operations. Referenced by:
    • std::noskipws()
    • std::__detail::operator>>()
    • std::philox_engine< uint_fast32_t, 32, 4, 10, 0xCD9E8D57, 0x9E3779B9, 0xD2511F53, 0xBB67AE85 >::operator>>
    • std::skipws()
  • const openmode std::ios_base::trunc [static], [inherited] — truncate an existing stream when opening. Default for ofstream. no referenced-by list for this one, she's doing her own thing 💅
  • const fmtflags std::ios_base::unitbuf [static], [inherited] — flushes output after each output operation. yes, every single one, she does not wait. Referenced by:
    • std::basic_ostream< _CharT, _Traits >::sentry::~sentry()
    • std::nounitbuf()
    • std::unitbuf()
  • const fmtflags std::ios_base::uppercase [static], [inherited] — replaces certain lowercase letters with their uppercase equivalents in generated output. she's loud and she knows it 📣 Referenced by:
    • std::num_put< _CharT, _OutIter >::do_put()
    • std::nouppercase()
    • std::uppercase()

👑 AUTHOR

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