Converts data according to a format and outputs it to the specified area.

[Format]

#include <stdarg.h>

#include <stdio.h>

long vsnprintf(char *restrict s, size_t n, const char *restrict control, va_list arg);

[Parameters]

s Pointer to storage area to which data is to be output

n Number of characters to be output

control Pointer to string indicating format

arg Parameter list

[Return values]

Number of characters converted

[Remarks]

The vsnprintf function is equivalent to snprintf with arg specified instead of the variable parameters.

Initialize arg through the va_start macro before calling the vsnprintf function.

The vsnprintf function does not call the va_end macro.