#include <libexplain/ac/errno.h>
#include <libexplain/ac/stdio.h>
#include <libexplain/buffer/errno/printf.h>
#include <libexplain/common_message_buffer.h>
#include <libexplain/printf.h>

Functions
const char *	explain_printf (const char *format,...)
const char *	explain_errno_printf (int errnum, const char *format,...)
void	explain_message_printf (char message, int message_size, const char format,...)
void	explain_message_errno_printf (char message, int message_size, int errnum, const char format,...)

Function Documentation

const char* explain_errno_printf	(	int	errnum,
		const char *	format,
			...
	)

The explain_errno_printf function is used to obtain an explanation of an error returned by the printf(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.

Parameters:

errnum	The error value to be decoded, usually obtained from the errno global variable just before this function is called. This is necessary if you need to call any code between the system call to be explained and this function, because many libc functions will alter the value of errno.
format	The original format, exactly as passed to the printf(3) system call.

Returns:: The message explaining the error. This message buffer is shared by all libexplain functions which do not supply a buffer in their argument list. This will be overwritten by the next call to any libexplain function which shares this buffer, including other threads.

Note:: This function is not thread safe, because it shares a return buffer across all threads, and many other functions in this library.

Example:

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

 errno = EINVAL;
 int result = printf(format, ...);
 if (result < 0)
 {
     int err = errno;
     fprintf(stderr, "%s\n", explain_errno_printf(err, format, ...));
     exit(EXIT_FAILURE);
 }

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

Definition at line 49 of file printf.c.

void explain_message_errno_printf	(	char *	message,
		int	message_size,
		int	errnum,
		const char *	format,
			...
	)

Definition at line 83 of file printf.c.

void explain_message_printf	(	char *	message,
		int	message_size,
		const char *	format,
			...
	)

Definition at line 68 of file printf.c.

const char* explain_printf	(	const char *	format,
			...
	)

The explain_printf function is used to obtain an explanation of an error returned by the printf(3) system call. The least the message will contain is the value of strerror(errno), 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:

format The original format, exactly as passed to the printf(3) system call.

Returns:: The message explaining the error. This message buffer is shared by all libexplain functions which do not supply a buffer in their argument list. This will be overwritten by the next call to any libexplain function which shares this buffer, including other threads.

Note:: This function is not thread safe, because it shares a return buffer across all threads, and many other functions in this library.

Example:

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

 errno = EINVAL;
 int result = printf(format, ...);
 if (result < 0)
 {
     fprintf(stderr, "%s\n", explain_printf(format, ...));
     exit(EXIT_FAILURE);
 }

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

Definition at line 28 of file printf.c.

Functions

Function Documentation