libexplain/message/setgroups.c File Reference

#include <libexplain/ac/errno.h>
#include <libexplain/ac/unistd.h>
#include <libexplain/setgroups.h>

Go to the source code of this file.

Functions
void	explain_message_setgroups (char *message, int message_size, size_t data_size, const gid_t *data)

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Function Documentation

void explain_message_setgroups	(	char *	message,
		int	message_size,
		size_t	data_size,
		const gid_t *	data
	)

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

Example:

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

 if (setgroups(data_size, data) < 0)
 {
     char message[3000];
     explain_message_setgroups(message, sizeof(message), data_size, data);
     fprintf(stderr, "%s\n", message);
     exit(EXIT_FAILURE);
 }

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

Definition at line 26 of file setgroups.c.