Header File 

stdio.h  

Category 

Memory and String Manipulation Routines 

Prototype 

int sprintf(char *buffer, const char *format[, argument, ...]); 

int swprintf(wchar_t *buffer, const wchar_t *format[, argument, ...]); 

Description 

Writes formatted output to a string.

sprintf applies the first format specifier to the first argument, the second to the second, and so on. There must be the same number of format specifiers as arguments. 

Return Value 

On success, sprintf returns the number of bytes output. The return value does not include the terminating null byte in the count.  

On error, sprintf returns EOF. 

Example  

#include <stdio.h>
#include <math.h>
int main(void)
{
   char buffer[80];
   sprintf(buffer, "An approximation of Pi is %f\n", M_PI);
   puts(buffer);
   return 0;
}

Portability