explain_tcdrain(3)

💖 explain_tcdrain — a whole manual, but make it make sense 💖

okay bestie, welcome to explain_tcdrain(3) from the Library Functions Manual. this is the page that tells you how to get actual, real, human-readable explanations when tcdrain(3) ghosts you with an error. no cap. 🫶

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✨ NAME ✨

explain_tcdrain — explain tcdrain(3) errors 💅

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🌸 SYNOPSIS 🌸

#include <libexplain/tcdrain.h>
const char *explain_tcdrain(int fildes);
const char *explain_errno_tcdrain(int errnum, int fildes);
void explain_message_tcdrain(char *message, int message_size, int
fildes);
void explain_message_errno_tcdrain(char *message, int message_size, int
errnum, int fildes);

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🦋 DESCRIPTION 🦋

so like, these functions? they're your little translators. you use them to obtain explanations for errors returned by the tcdrain(3) system call. it's giving "error message but with lore". ✨

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🎀 explain_tcdrain 🎀

const char *explain_tcdrain(int fildes);

the explain_tcdrain function is used to obtain an explanation of an error returned by the tcdrain(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, we love to see 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 tcdrain(3) system call. yes, exactly. we don't do remixes here. 🎀

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. so like… don't get attached, she's not yours alone. 😭

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

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

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

the above code example is available pre‐packaged as the explain_tcdrain_or_die(3) function. iconic behaviour, honestly. 👑

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🧚 explain_errno_tcdrain 🧚

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

the explain_errno_tcdrain function is used to obtain an explanation of an error returned by the tcdrain(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. fr fr. ✨

• 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 like, grab it before anything else touches it, bestie. 🫶
• fildes — the original fildes, exactly as passed to the tcdrain(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. same energy as before, no cap. 💀

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

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

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

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🌈 explain_message_tcdrain 🌈

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

the explain_message_tcdrain function is used to obtain an explanation of an error returned by the tcdrain(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. it's giving thorough. 🌸

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, being all responsible. 🥹
• message_size — the size in bytes of the location in which to store the returned message.
• fildes — the original fildes, exactly as passed to the tcdrain(3) system call.

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

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

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

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💜 explain_message_errno_tcdrain 💜

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

the explain_message_errno_tcdrain function is used to obtain an explanation of an error returned by the tcdrain(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. she ate and left no crumbs. 💅

• 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. catch it quick, girlie. 🏃‍♀️
• fildes — the original fildes, exactly as passed to the tcdrain(3) system call.

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

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

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

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🔥 SEE ALSO 🔥

• tcdrain(3) — execute tcdrain(3)
• explain_tcdrain_or_die(3) — execute tcdrain(3) and report errors

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👑 COPYRIGHT 👑

okay that's the whole page bestie, you made it to the end, main character energy honestly. this was libexplain version 1.4, copyright (C) 2009 Peter Miller. 🎀✨🦋 thanks for reading, go forth and explain your errors. 💖