explain_bind(3)

💖 explain_bind(3) — the group chat guide to decoding bind(2) drama 💖

okay so bestie, this is a page from the Library Functions Manual, and it's all about explain_bind — the friend who tells you why your bind(2) call is out here failing. no cap. ✨

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🌸 NAME 🌸

explain_bind — explain bind(2) errors. that's it. that's the whole job. and it does it so well. 💅

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🎀 SYNOPSIS 🎀

#include <libexplain/bind.h>
const char *explain_bind(int fildes, const struct sockaddr *sock_addr,
       int sock_addr_size);
const char *explain_errno_bind(int errnum, int fildes, const struct
       sockaddr *sock_addr, int sock_addr_size);
void explain_message_bind(char *message, int message_size, int fildes,
       const struct sockaddr *sock_addr, int sock_addr_size);
void explain_message_errno_bind(char *message, int message_size, int
       errnum, int fildes, const struct sockaddr *sock_addr, int
       sock_addr_size);

four functions. four besties. all of them here to translate your socket suffering into words. 🫶

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✨ DESCRIPTION ✨

so like, these functions may be used to obtain explanations for errors returned by the bind(2) system call. that's the whole vibe. you got an error, you want to know what it means, you call one of these.

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🦋 explain_bind 🦋

const char *explain_bind(int fildes, const struct sockaddr *sock_addr,
       int sock_addr_size);

the explain_bind function is used to obtain an explanation of an error returned by the bind(2) system call. and listen — 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 overachiever. we love that for it. 💖

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

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

if (bind(fildes, sock_addr, sock_addr_size) < 0)
{
    fprintf(stderr, "%s\n",
        explain_bind(fildes, sock_addr, sock_addr_size));
    exit(EXIT_FAILURE);
}

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

• fildes — the original fildes, exactly as passed to the bind(2) system call. literally exactly. don't get cute with it.
• sock_addr — the original sock_addr, exactly as passed to the bind(2) system call.
• sock_addr_size — the original sock_addr_size, exactly as passed to the bind(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. so like... be careful, bestie. 🚨

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🌈 explain_errno_bind 🌈

const char *explain_errno_bind(int errnum, int fildes, const struct
       sockaddr *sock_addr, int sock_addr_size);

the explain_errno_bind function is used to obtain an explanation of an error returned by the bind(2) system call. the least the message will contain is the value of strerror(errnum), but usually it will do much better, and indicate the underlying cause in more detail. iconic behaviour fr fr. ✨

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

if (bind(fildes, sock_addr, sock_addr_size) < 0)
{
    int err = errno;
    fprintf(stderr, "%s\n", explain_errno_bind(err,
        fildes, sock_addr, sock_addr_size));
    exit(EXIT_FAILURE);
}

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

• 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, save it first, okay? don't let it get away from you. 😭
• fildes — the original fildes, exactly as passed to the bind(2) system call.
• sock_addr — the original sock_addr, exactly as passed to the bind(2) system call.
• sock_addr_size — the original sock_addr_size, exactly as passed to the bind(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. 💀

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🌸 explain_message_bind 🌸

void explain_message_bind(char *message, int message_size, int fildes,
       const struct sockaddr *sock_addr, int sock_addr_size);

the explain_message_bind function may be used to obtain an explanation of an error returned by the bind(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. she's thorough. she's giving main character energy. 👑

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

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

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

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

• message — the location in which to store the returned message. if a suitable message return buffer is supplied, this function is thread safe. yes bestie, YOU can be the thread-safe one. it's your moment. 💅
• 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 bind(2) system call.
• sock_addr — the original sock_addr, exactly as passed to the bind(2) system call.
• sock_addr_size — the original sock_addr_size, exactly as passed to the bind(2) system call.

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💜 explain_message_errno_bind 💜

void explain_message_errno_bind(char *message, int message_size, int
       errnum, int fildes, const struct sockaddr *sock_addr, int
       sock_addr_size);

the explain_message_errno_bind function may be used to obtain an explanation of an error returned by the bind(2) system call. the least the message will contain is the value of strerror(errnum), but usually it will do much better, and indicate the underlying cause in more detail. the most extra of the four, honestly, and we stan. 🌟

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

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

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

• 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. again. i'm telling you. save errno first. 🙈
• fildes — the original fildes, exactly as passed to the bind(2) system call.
• sock_addr — the original sock_addr, exactly as passed to the bind(2) system call.
• sock_addr_size — the original sock_addr_size, exactly as passed to the bind(2) system call.

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👀 SEE ALSO 👀

• bind(2) — bind a name to a socket
• explain_bind_or_die(3) — bind a name to a socket and report errors

iykyk. go read those next. 🦋

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📜 COPYRIGHT 📜

libexplain version 1.4
Copyright (C) 2008 Peter Miller

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okay that's the whole page bestie, you're officially educated 💖 now go forth and bind responsibly. periodt. 👑

signed off with love — libexplain version 1.4, © 2008 Peter Miller, and this page's lil footer tag explain_bind(3) 🎀