explain_opendir(3)

✨ NAME ✨

explain_opendir — bestie, this is the page that translates your opendir(3) errors into actual human words 💅

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🦋 SYNOPSIS 🦋

const char *explain_opendir(const char *pathname);
const char *explain_errno_opendir(int errnum, const char *pathname); int
errnum, const char *pathname);
void explain_message_opendir(char *message, int message_size,
void explain_message_errno_opendir(char *message, int message_size,
const char *pathname);

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🌸 DESCRIPTION 🌸

Okay so these functions? They're here to explain your opendir(3) errors. Like, the whole point is that you don't have to sit there squinting at a raw error number wondering what went wrong. Iconic behaviour, honestly.

🎀 explain_opendir

const char *explain_opendir(const char *pathname);

The explain_opendir function gets you an explanation of an error that came back from the opendir(3) function. The least the message will contain is the value of strerror(errno), but usually it goes way harder than that and tells you the actual underlying cause in more detail. Lowkey overachiever energy and we love that 💖

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:

DIR *dp = opendir(pathname);
if (!dp)
{
    fprintf(stderr, "%s\n", explain_opendir(pathname));
    exit(EXIT_FAILURE);
}

pathname

The original pathname, exactly as passed to the opendir(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. So like… if you're threading, be careful bestie 🫠

🦋 explain_errno_opendir

const char *explain_errno_opendir(int errnum, const char *pathname); int
errnum, const char *pathname);

The explain_errno_opendir function gets you an explanation of an error returned by the opendir(3) function. The least the message will contain is the value of strerror(errnum), but usually it does much better and points at the underlying cause in more detail. Periodt.

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

DIR *dp = opendir(pathname);
if (!dp)
{
    int errnum = errno;
    const char *message = explain_errno_opendir(errnum, pathname);
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

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. Rude of them honestly 😭

pathname

The original pathname, exactly as passed to the opendir(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.

💜 explain_message_opendir

void explain_message_opendir(char *message, int message_size, const char
*pathname);

The explain_message_opendir function gets you an explanation of an error returned by the opendir(3) function. The least the message will contain is the value of strerror(errno), but usually it does much better and indicates the underlying cause in more detail.

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:

DIR *dp = opendir(pathname);
if (!dp)
{
    char message[3000];
    explain_message_opendir(message, sizeof(message), pathname);
    fprintf(stderr, "%s\n", message);
    exit(EXIT_FAILURE);
}

message

The location in which to store the returned message. Because a message return buffer has been supplied, this function is thread safe if the buffer is thread safe. You brought your own buffer, so you're the main character now 👑

message_size

The size in bytes of the location in which to store the returned message.

pathname

The original pathname, exactly as passed to the opendir(3) system call.

🌈 explain_message_errno_opendir

void explain_message_errno_opendir(char *message, int message_size,
const char *pathname);

The explain_message_errno_opendir function gets you an explanation of an error returned by the opendir(3) function. The least the message will contain is the value of strerror(errnum), but usually it does much better and indicates the underlying cause in more detail.

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

DIR *dp = opendir(pathname);
if (!dp);
{
    int err = errno;
    char message[3000];
    explain_message_errno_opendir(message, sizeof(message), err,
        pathname);
    fprintf(stderr, '%s\n', message);
    exit(EXIT_FAILURE);
}

message

The location in which to store the returned message. Because a message return buffer has been supplied, this function is thread safe if the buffer 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.

pathname

The original pathname, exactly as passed to the opendir(3) system call.

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💖 COPYRIGHT 💖

libexplain version 1.4

Copyright (C) 2008 Peter Miller

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🫶 AUTHOR 🫶

Written by Peter Miller <pmiller@opensource.org.au>

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ok that's the whole thing bestie, no notes, ate and left no crumbs 💅✨ so this was libexplain version 1.4, Copyright (C) 2008 Peter Miller, and you've been reading explain_opendir(3) — go forth and debug, you absolute icon 🎀🦋