explain_setsid(3)

💖 explain_setsid(3) — Library Functions Manual 💖

okay so bestie, welcome to explain_setsid(3), your new fave little helper from the Library Functions Manual that turns setsid(2) heartbreak into actual readable words 💅

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✨ NAME ✨

explain_setsid — explain setsid(2) errors 🫶

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🌸 SYNOPSIS 🌸

#include <libexplain/setsid.h>
const char *explain_setsid(void);
const char *explain_errno_setsid(int errnum, void);
void explain_message_setsid(char *message, int message_size, void);
void explain_message_errno_setsid(char *message, int message_size, int
errnum, void);

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🦋 DESCRIPTION 🦋

These functions are the whole vibe when you need explanations for errors that the setsid(2) system call threw back at you. It's giving "translator for your syscall's cryptic tantrums" ✨

💜 explain_setsid

const char *explain_setsid(void);

The explain_setsid function is what you call to get an explanation of an error returned by the setsid(2) system call. The absolute bare minimum it'll give you is the value of strerror(errno), but ngl it usually does so much better than that and actually tells you the underlying cause in more detail 👑

The errno global variable is the one it reads to get the error value that needs decoding, no cap.

Returns:

• The message explaining the error. Heads up bestie, this message buffer is shared by all the 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 — other threads included. main character energy but the chaotic kind 😭

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

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

pid_t result = setsid();
if (result < 0)
{
    fprintf(stderr, "%s\n", explain_setsid());
    exit(EXIT_FAILURE);
}

The above code example is available pre-packaged as the explain_setsid_or_die(3) function 🎀

🌈 explain_errno_setsid

const char *explain_errno_setsid(int errnum, void);

The explain_errno_setsid function is used to obtain an explanation of an error returned by the setsid(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 ✨

• errnum — the error value to be decoded, usually snagged from the errno global variable right before you call this function. This is necessary if you need to call any code between the system call being explained and this function, because so many libc functions will alter the value of errno (sneaky fr fr).

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:

pid_t result = setsid();
if (result < 0)
{
    int err = errno;
    fprintf(stderr, "%s\n", explain_errno_setsid(err, ));
    exit(EXIT_FAILURE);
}

The above code example is available pre-packaged as the explain_setsid_or_die(3) function 🌸

🧚 explain_message_setsid

void explain_message_setsid(char *message, int message_size, void);

The explain_message_setsid function is used to obtain an explanation of an error returned by the setsid(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 👑
• message_size — the size in bytes of the location in which to store the returned message.

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

pid_t result = setsid();
if (result < 0)
{
    char message[3000];
    explain_message_setsid(message, sizeof(message), );
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

The above code example is available pre-packaged as the explain_setsid_or_die(3) function ⭐

🍓 explain_message_errno_setsid

void explain_message_errno_setsid(char *message, int message_size, int
errnum, void);

The explain_message_errno_setsid function is used to obtain an explanation of an error returned by the setsid(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 🔥

• 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 🙈

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

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

The above code example is available pre-packaged as the explain_setsid_or_die(3) function 🦋

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👀 SEE ALSO 👀

• setsid(2) — creates a session and sets the process group ID
• explain_setsid_or_die(3) — creates a session and sets the process group ID and report errors

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💅 COPYRIGHT 💅

libexplain version 1.4 Copyright (C) 2011 Peter Miller

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and that's the whole page bestie, tysm for reading 🫶 the footer said explain_setsid(3) on it and everything, so you know it's the real deal. slay, go explain those errors 💖✨🎀