explain_getw(3)

💖 explain_getw(3) — the libexplain glow-up for getw(3) errors 💖

okay so bestie, welcome to explain_getw(3) from the Library Functions Manual ✨. This is the libexplain page that tells you how to get actual explanations for errors that getw(3) throws at you, instead of just staring at a cryptic number like it's a cryptic number 💀. Buckle up, it's giving helpful and it's giving iconic.

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🌸 NAME 🌸

explain_getw — explain getw(3) errors 🫶

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✨ SYNOPSIS ✨

#include <libexplain/getw.h>
const char *explain_getw(FILE *fp);
const char *explain_errno_getw(int errnum, FILE *fp);
void explain_message_getw(char *message, int message_size, FILE *fp);
void explain_message_errno_getw(char *message, int message_size, int
errnum, FILE *fp);

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🦋 DESCRIPTION 🦋

These functions may be used to obtain explanations for errors returned by the getw(3) system call. That's the whole vibe. Four little helpers, all obsessed with telling you why things went wrong 💅.

💜 explain_getw

const char *explain_getw(FILE *fp);

The explain_getw function is used to obtain an explanation of an error returned by the getw(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. Like, it's not just gonna hand you a shrug emoji, it's gonna give you the whole story 🔥.

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

• fp — the original fp, exactly as passed to the getw(3) system call. No copies, no edits, no remixes — the exact same pointer, bestie.

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. So like... one at a time, babes 🙈.

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

int result = getw(fp);
if (result < 0)
{
    fprintf(stderr, "%s\n", explain_getw(fp));
    exit(EXIT_FAILURE);
}

The above code example is available pre‐packaged as the explain_getw_or_die(3) function. Slay, they already did the work for you ✨.

🎀 explain_errno_getw

const char *explain_errno_getw(int errnum, FILE *fp);

The explain_errno_getw function is used to obtain an explanation of an error returned by the getw(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.

• 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. Like, errno is fragile, bestie, capture it while it's still valid 📸.
• fp — the original fp, exactly as passed to the getw(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:

int result = getw(fp);
if (result < 0)
{
    int err = errno;
    fprintf(stderr, "%s\n", explain_errno_getw(err, fp));
    exit(EXIT_FAILURE);
}

The above code example is available pre‐packaged as the explain_getw_or_die(3) function.

🌈 explain_message_getw

void explain_message_getw(char *message, int message_size, FILE *fp);

The explain_message_getw function is used to obtain an explanation of an error returned by the getw(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 you, being all responsible with your own buffer 👑.
• message_size — the size in bytes of the location in which to store the returned message.
• fp — the original fp, exactly as passed to the getw(3) system call.

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

int result = getw(fp);
if (result < 0)
{
    char message[3000];
    explain_message_getw(message, sizeof(message), fp);
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

The above code example is available pre‐packaged as the explain_getw_or_die(3) function.

🧚 explain_message_errno_getw

void explain_message_errno_getw(char *message, int message_size, int
errnum, FILE *fp);

The explain_message_errno_getw function is used to obtain an explanation of an error returned by the getw(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.

• 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.
• fp — the original fp, exactly as passed to the getw(3) system call.

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

int result = getw(fp);
if (result < 0)
{
    int err = errno;
    char message[3000];
    explain_message_errno_getw(message, sizeof(message), err,
    fp);
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

The above code example is available pre‐packaged as the explain_getw_or_die(3) function.

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👑 SEE ALSO 👑

• getw(3) — input a word (int) 🌸
• explain_getw_or_die(3) — input a word (int) and report errors 💅

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💖 COPYRIGHT 💖

libexplain version 1.4 Copyright (C) 2010 Peter Miller

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and that's the whole page, bestie 🎀 fr fr, go forth and decode your errno like the main character you are. this was the explain_getw(3) page, from Library Functions Manual, libexplain version 1.4, copyright 2010 Peter Miller — mwah, take care of your file pointers 💜🦋✨