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);