DOKK / manpages / debian 11 / libexplain-dev / explain_vsprintf_or_die.3.en
explain_vsprintf_or_die(3) Library Functions Manual explain_vsprintf_or_die(3)

explain_vsprintf_or_die - formatted output conversion and report errors

#include <libexplain/vsprintf.h>

int explain_vsprintf_or_die(char *data, const char *format, va_list ap);
int explain_vsprintf_on_error(char *data, const char *format, va_list ap);

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

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

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

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

The explain_vsprintf_on_error function always returns the value return by the wrapped vsprintf(3) system call.

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

int result = explain_vsprintf_or_die(data, format, ap);

vsprintf(3)
formatted output conversion
explain_vsprintf(3)
explain vsprintf(3) errors
exit(2)
terminate the calling process

libexplain version 1.4
Copyright (C) 2010 Peter Miller