libexplain/message/strtoul.c File Reference

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

Go to the source code of this file.

Functions
void	explain_message_strtoul (char *message, int message_size, const char *nptr, char **endptr, int base)

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Function Documentation

void explain_message_strtoul	(	char *	message,
		int	message_size,
		const char *	nptr,
		char **	endptr,
		int	base
	)

The explain_message_strtoul function is used to obtain an explanation of an error returned by the strtoul(3) 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.
nptr	The original nptr, exactly as passed to the strtoul(3) system call.
endptr	The original endptr, exactly as passed to the strtoul(3) system call.
base	The original base, exactly as passed to the strtoul(3) system call.

Example:

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

 unsigned long result = strtoul(nptr, endptr, base);
 if (result < 0)
 {
     char message[3000];
     explain_message_strtoul(message, sizeof(message), nptr, endptr, base);
     fprintf(stderr, "%s\n", message);
     exit(EXIT_FAILURE);
 }

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

Definition at line 25 of file strtoul.c.