xsprintf.h File Reference

The xsnprintf() and xvsnprintf() functions are equivalent to ISO C99's snprintf() and vsnprintf(). More...

Functions
int	xsnprintf (char *restrict str, size_t size, const char *restrict format,...) __attribute__((format(printf
	The xsnprintf() function is equivalent to ISO C99's snprintf().
int int	xvsnprintf (char *restrict str, size_t size, const char *restrict format, va_list ap)
	The xvsnprintf() function is equivalent to ISO C99's vsnprintf().

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Detailed Description

The xsnprintf() and xvsnprintf() functions are equivalent to ISO C99's snprintf() and vsnprintf().

The functions behave as xprintf(), except that the output is written into an array (specified by argument str) rather than to a channel.

If size is zero, nothing is written, and str may be a null pointer. Otherwise, output characters beyond the size-1st are discarded rather than being written to the array, and a null character is written at the end of the characters actually written into the array.

Thus, the null terminated output has been completely written if and only if the returned value is nonnegative and less than size.

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Function Documentation

int xsnprintf	(	char *restrict	str,
		size_t	size,
		const char *restrict	format,
			...
	)

The xsnprintf() function is equivalent to ISO C99's snprintf().

Parameters:

str	pointer to destination buffer
size	sizeof str
format	a printf() compatible format string
...	variable argument list for format

Returns:

<0: error code
≥0: the number of characters that would have been written had size been sufficiently large, not counting the terminating null character

See also:

snprintf() specification in ISO C99

int int xvsnprintf	(	char *restrict	str,
		size_t	size,
		const char *restrict	format,
		va_list	ap
	)

The xvsnprintf() function is equivalent to ISO C99's vsnprintf().

Parameters:

str	pointer to destination buffer
size	sizeof str
format	a printf() compatible format string
ap	va_list to the arguments for format

Returns:

<0: error code
≥0: the number of characters that would have been written had size been sufficiently large, not counting the terminating null character

See also:

vsnprintf() specification in ISO C99