libexplain  1.4.D001
Functions
libexplain/message/setsockopt.c File Reference
#include <libexplain/ac/errno.h>
#include <libexplain/ac/sys/socket.h>
#include <libexplain/setsockopt.h>

Go to the source code of this file.

Functions

void explain_message_setsockopt (char *message, int message_size, int fildes, int level, int name, void *data, socklen_t data_size)

Function Documentation

void explain_message_setsockopt ( char *  message,
int  message_size,
int  fildes,
int  level,
int  name,
void *  data,
socklen_t  data_size 
)

The explain_message_setsockopt function is used to obtain an explanation of an error returned by the setsockopt(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.

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

 if (setsockopt(fildes, level, name, data, data_size) < 0)
 {
     char message[3000];
     explain_message_setsockopt(message, sizeof(message), fildes, level,
         name, data, data_size);
     fprintf(stderr, "%s\n", message);
     exit(EXIT_FAILURE);
 }

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

Parameters:
messageThe location in which to store the returned message. If a suitable message return buffer is supplied, this function is thread safe.
message_sizeThe size in bytes of the location in which to store the returned message.
fildesThe original fildes, exactly as passed to the setsockopt(2) system call.
levelThe original level, exactly as passed to the setsockopt(2) system call.
nameThe original name, exactly as passed to the setsockopt(2) system call.
dataThe original data, exactly as passed to the setsockopt(2) system call.
data_sizeThe original data_size, exactly as passed to the setsockopt(2) system call.

Definition at line 26 of file setsockopt.c.