libexplain  1.4.D001
Functions
libexplain/dup.c File Reference
#include <libexplain/ac/errno.h>
#include <libexplain/dup.h>

Go to the source code of this file.

Functions

const char * explain_dup (int fildes)

Function Documentation

const char* explain_dup ( int  fildes)

The explain_dup function is used to obtain an explanation of an error returned by the dup(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.

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

 int newfd = dup(fildes);
 if (newfd < 0)
 {
     fprintf(stderr, "%s\n", explain_dup(fildes));
     exit(EXIT_FAILURE);
 }

The above code example is available pre-packaged as the explain_dup_or_die function.

Parameters:
fildesThe original fildes, exactly as passed to the dup(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.

Definition at line 25 of file dup.c.