explain_iconv_open(3)

✨ explain_iconv_open(3) — bestie edition 💖

okay so real talk, this is a page from the Library Functions Manual about explain_iconv_open(3), and honestly? it's a whole vibe. it's all about turning those cryptic iconv_open(3) failures into actual sentences a human can read. no cap.

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🌸 NAME 🌸

explain_iconv_open — explain iconv_open(3) errors 🫶

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✨ SYNOPSIS ✨

#include <libexplain/iconv_open.h>
const char *explain_iconv_open(const char *tocode, const char
*fromcode);
const char *explain_errno_iconv_open(int errnum, const char *tocode,
const char *fromcode);
void explain_message_iconv_open(char *message, int message_size, const
char *tocode, const char *fromcode);
void explain_message_errno_iconv_open(char *message, int message_size,
int errnum, const char *tocode, const char *fromcode);

like, four whole functions. one header. slay. 💅

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👑 DESCRIPTION 👑

so these functions? they exist so you can get explanations for errors that the iconv_open(3) system call throws at you. that's it. that's the job. ✨

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🌈 explain_iconv_open

const char *explain_iconv_open(const char *tocode, const char
*fromcode);

the explain_iconv_open function is your go-to for getting an explanation of an error that came back from the iconv_open(3) system call. the least it's gonna give you is the value of strerror(errno) — but usually it does so much better and points at the underlying cause in way more detail. it ate, honestly.

the errno global variable is what gets used to grab the error value that's gonna be decoded.

• tocode — the original tocode, exactly as passed to the iconv_open(3) system call. don't touch it, don't "fix" it, just hand it over as-is. 🙈
• fromcode — the original fromcode, exactly as passed to the iconv_open(3) system call. same energy. 💜

Returns: the message explaining the error. this message buffer is shared by all libexplain functions that don't supply a buffer in their argument list. it's gonna get overwritten by the next call to any libexplain function that shares this buffer, including calls from other threads. so like… don't get attached. 😭

Note: this function is not thread safe, because it shares a return buffer across all threads, and so do many other functions in this library. periodt.

Example: this function is meant to be used in a fashion similar to the following example:

iconv_t result = iconv_open(tocode, fromcode);
if (result < 0)
{
    fprintf(stderr, "%s\n", explain_iconv_open(tocode,
    fromcode));
    exit(EXIT_FAILURE);
}

the above code example is available pre-packaged as the explain_iconv_open_or_die(3) function. iconic behaviour, fr fr.

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🦋 explain_errno_iconv_open

const char *explain_errno_iconv_open(int errnum, const char *tocode,
const char *fromcode);

the explain_errno_iconv_open function is used to obtain an explanation of an error returned by the iconv_open(3) system call. the least the message will contain is the value of strerror(errno), but usually it will do much better, and indicate the underlying cause in more detail. highkey overachieving. 💅

• errnum — the error value to be decoded, usually grabbed from the errno global variable just before this function is called. this is necessary if you need to call any code between the system call to be explained and this function, because many libc functions will alter the value of errno. so like, save it first bestie. 🫶
• tocode — the original tocode, exactly as passed to the iconv_open(3) system call.
• fromcode — the original fromcode, exactly as passed to the iconv_open(3) system call.

Returns: the message explaining the error. this message buffer is shared by all libexplain functions which do not supply a buffer in their argument list. this will be overwritten by the next call to any libexplain function which shares this buffer, including other threads.

Note: this function is not thread safe, because it shares a return buffer across all threads, and many other functions in this library.

Example: this function is intended to be used in a fashion similar to the following example:

iconv_t result = iconv_open(tocode, fromcode);
if (result < 0)
{
    int err = errno;
    fprintf(stderr, "%s\n", explain_errno_iconv_open(err, tocode,
    fromcode));
    exit(EXIT_FAILURE);
}

the above code example is available pre-packaged as the explain_iconv_open_or_die(3) function.

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🎀 explain_message_iconv_open

void explain_message_iconv_open(char *message, int message_size, const
char *tocode, const char *fromcode);

the explain_message_iconv_open function is used to obtain an explanation of an error returned by the iconv_open(3) system call. the least the message will contain is the value of strerror(errno), but usually it will do much better, and indicate the underlying cause in more detail.

the errno global variable will be used to obtain the error value to be decoded.

• message — the location in which to store the returned message. if a suitable message return buffer is supplied, this function is thread safe. look at her go!! 👑
• message_size — the size in bytes of the location in which to store the returned message.
• tocode — the original tocode, exactly as passed to the iconv_open(3) system call.
• fromcode — the original fromcode, exactly as passed to the iconv_open(3) system call.

Example: this function is intended to be used in a fashion similar to the following example:

iconv_t result = iconv_open(tocode, fromcode);
if (result < 0)
{
    char message[3000];
    explain_message_iconv_open(message, sizeof(message), tocode,
    fromcode);
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

the above code example is available pre-packaged as the explain_iconv_open_or_die(3) function.

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🍓 explain_message_errno_iconv_open

void explain_message_errno_iconv_open(char *message, int message_size,
int errnum, const char *tocode, const char *fromcode);

the explain_message_errno_iconv_open function is used to obtain an explanation of an error returned by the iconv_open(3) system call. the least the message will contain is the value of strerror(errno), but usually it will do much better, and indicate the underlying cause in more detail. the way she just knows things 💀

• message — the location in which to store the returned message. if a suitable message return buffer is supplied, this function is thread safe.
• message_size — the size in bytes of the location in which to store the returned message.
• errnum — the error value to be decoded, usually obtained from the errno global variable just before this function is called. this is necessary if you need to call any code between the system call to be explained and this function, because many libc functions will alter the value of errno. grab it early or lose it. 😤
• tocode — the original tocode, exactly as passed to the iconv_open(3) system call.
• fromcode — the original fromcode, exactly as passed to the iconv_open(3) system call.

Example: this function is intended to be used in a fashion similar to the following example:

iconv_t result = iconv_open(tocode, fromcode);
if (result < 0)
{
    int err = errno;
    char message[3000];
    explain_message_errno_iconv_open(message, sizeof(message),
    err, tocode, fromcode);
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

the above code example is available pre-packaged as the explain_iconv_open_or_die(3) function.

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💜 SEE ALSO 💜

• iconv_open(3) — allocate descriptor for character set conversion
• explain_iconv_open_or_die(3) — allocate descriptor for character set conversion and report errors

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🌟 COPYRIGHT 🌟

libexplain version 1.4 Copyright (C) 2013 Peter Miller

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and that's the whole page bestie!! you made it to the end, main character energy fr 🧚✨ this was explain_iconv_open(3) from the Library Functions Manual — libexplain version 1.4, © 2013 Peter Miller. go forth and decode your errors, you've got this. 💖🎀🦋