libexplain/message/eventfd.c File Reference

#include <libexplain/ac/errno.h>
#include <libexplain/eventfd.h>

Go to the source code of this file.

Functions
void	explain_message_eventfd (char *message, int message_size, unsigned int initval, int flags)

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Function Documentation

void explain_message_eventfd	(	char *	message,
		int	message_size,
		unsigned int	initval,
		int	flags
	)

The explain_message_eventfd function is used to obtain an explanation of an error returned by the eventfd(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 errno global variable will be used to obtain the error value to be decoded.

Parameters:

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.
initval	The original initval, exactly as passed to the eventfd(2) system call.
flags	The original flags, exactly as passed to the eventfd(2) system call.

Example:

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

 int result = eventfd(initval, flags);
 if (result < 0)
 {
     char message[3000];
     explain_message_eventfd(message, sizeof(message), initval, flags);
     fprintf(stderr, "%s\n", message);
     exit(EXIT_FAILURE);
 }

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

Definition at line 25 of file eventfd.c.