explain_fsync(3)

✨ explain_fsync — the manual page, but make it make sense ✨

okay bestie, welcome to the explain_fsync(3) glow-up 💖 this is a page from the Library Functions Manual, and it's basically your emotional support error-decoder for fsync(2). no cap.

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🌸 NAME 🌸

explain_fsync — explain fsync(2) errors 💅

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🎀 SYNOPSIS 🎀

#include <libexplain/fsync.h>
const char *explain_fsync(int fildes);
const char *explain_errno_fsync(int errnum, int fildes);
void explain_message_fsync(char *message, int message_size, int fildes);
void explain_message_errno_fsync(char *message, int message_size, int
errnum, int fildes);

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🦋 DESCRIPTION 🦋

so these functions? they exist to hand you explanations for errors that come back from the fsync(2) system call. that's it, that's the whole job. icon behaviour honestly 👑

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💜 explain_fsync

const char *explain_fsync(int fildes);

the explain_fsync function is here to get you an explanation of an error returned by the fsync(2) system call. the least the message will contain is the value of strerror(errno), but usually it does much better than that and tells you the underlying cause in more detail. it's giving overachiever, and we love that for it ✨

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

• fildes — the original fildes, exactly as passed to the fsync(2) system call. don't get cute, don't modify it, just pass it through 🫶

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. it will be overwritten by the next call to any libexplain function which shares this buffer, including other threads. so like. don't hold onto it, bestie, it's not yours 😭

Note: this function is not thread safe, because it shares a return buffer across all threads, and many other functions in this library. yes, all of them. the whole squad shares one buffer. it's a group chat, not a DM. 💀

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

if (fsync(fildes) < 0)
{
    fprintf(stderr, "%s\n", explain_fsync(fildes));
    exit(EXIT_FAILURE);
}

the above code example is available pre‐packaged as the explain_fsync_or_die(3) function. yes, "or die" — main character energy fr fr 🔥

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🌈 explain_errno_fsync

const char *explain_errno_fsync(int errnum, int fildes);

the explain_errno_fsync function is used to obtain an explanation of an error returned by the fsync(2) 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. same energy, extra parameter, no notes 💅

• 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. so grab errno early, bestie, before something else snatches it 🏃♀️
• fildes — the original fildes, exactly as passed to the fsync(2) 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. screaming, crying, sharing one buffer 😭

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

if (fsync(fildes) < 0)
{
    int err = errno;
    fprintf(stderr, "%s\n", explain_errno_fsync(err, fildes));
    exit(EXIT_FAILURE);
}

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

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🌸 explain_message_fsync

void explain_message_fsync(char *message, int message_size, int fildes);

the explain_message_fsync function is used to obtain an explanation of an error returned by the fsync(2) 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. size matters, obviously 💅
• fildes — the original fildes, exactly as passed to the fsync(2) system call.

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

if (fsync(fildes) < 0)
{
    char message[3000];
    explain_message_fsync(message, sizeof(message), fildes);
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

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

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🧚 explain_message_errno_fsync

void explain_message_errno_fsync(char *message, int message_size, int
errnum, int fildes);

the explain_message_errno_fsync function is used to obtain an explanation of an error returned by the fsync(2) 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. it's the whole squad in one function, honestly 🌈

• 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.
• fildes — the original fildes, exactly as passed to the fsync(2) system call.

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

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

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

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⭐ SEE ALSO ⭐

• fsync(2) — synchronize a file's in‐core state with storage device. the original. the blueprint. the moment. 🫶
• explain_fsync_or_die(3) — synchronize a file's in‐core state with storage device and report errors. same vibe, but it also handles the reporting for you so you can go touch grass 🌱

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💖 COPYRIGHT 💖

libexplain version 1.4 Copyright (C) 2009 Peter Miller

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and that's the whole page bestie, you ate that 🍓 tysm for reading, mwah 💋 — explain_fsync(3), Library Functions Manual, libexplain version 1.4, Copyright (C) 2009 Peter Miller, signing off 🎀✨