explain_vsnprintf_or_die(3)

formatted output conversion and report errors

Section 3 libexplain-dev bookworm source

Description

explain_vsnprintf_or_die

NAME

explain_vsnprintf_or_die - formatted output conversion and report errors

SYNOPSIS

#include <libexplain/vsnprintf.h>
int explain_vsnprintf_or_die(char *data, size_t data_size, const char *format, va_list ap);
int explain_vsnprintf_on_error(char *data, size_t data_size, const char *format, va_list ap);

DESCRIPTION

The explain_vsnprintf_or_die function is used to call the vsnprintf(3) system call. On failure an explanation will be printed to stderr, obtained from the explain_vsnprintf(3) function, and then the process terminates by calling exit(EXIT_FAILURE).

The explain_vsnprintf_on_error function is used to call the vsnprintf(3) system call. On failure an explanation will be printed to stderr, obtained from the explain_vsnprintf(3) function, but still returns to the caller.

data

The data, exactly as to be passed to the vsnprintf(3) system call.

data_size

The data_size, exactly as to be passed to the vsnprintf(3) system call.

	format		The format, exactly as to be passed to the vsnprintf(3) system call.
	ap		The ap, exactly as to be passed to the vsnprintf(3) system call.

RETURN VALUE

The explain_vsnprintf_or_die function only returns on success, see vsnprintf(3) for more information. On failure, prints an explanation and exits, it does not return.

The explain_vsnprintf_on_error function always returns the value return by the wrapped vsnprintf(3) system call.

EXAMPLE

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

int result = explain_vsnprintf_or_die(data, data_size, format, ap);