libexplain/message/writev.c File Reference

#include <libexplain/ac/errno.h>
#include <libexplain/ac/sys/types.h>
#include <libexplain/ac/sys/uio.h>
#include <libexplain/writev.h>

Go to the source code of this file.

Functions
void	explain_message_writev (char *message, int message_size, int fildes, const struct iovec *data, int data_size)

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Function Documentation

void explain_message_writev	(	char *	message,
		int	message_size,
		int	fildes,
		const struct iovec *	data,
		int	data_size
	)

The explain_message_writev function is used to obtain an explanation of an error returned by the writev(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.
fildes	The original fildes, exactly as passed to the writev(2) system call.
data	The original data, exactly as passed to the writev(2) system call.
data_size	The original data_size, exactly as passed to the writev(2) system call.

Example:

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

 ssize_t result = writev(fildes, data, data_size);
 if (result < 0)
 {
     char message[3000];
     explain_message_writev(message, sizeof(message), fildes, data,
         data_size);
     fprintf(stderr, "%s\n", message);
     exit(EXIT_FAILURE);
 }

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

Definition at line 27 of file writev.c.