fprintf

---

defined in header file stdio.h

int fprintf( FILE * fileStream, const char * strFormat, ...);

The fprintf function sends formatted out put to stream, pointed by fileStream.

Parameters

Parameter	Description
fileStream	Pointer to a FILE object that identified by the stream.
strFormat	The string format that contains the text to be written to the stream. The format string is composed of zero or more directives

Returns

on successful, these function return the number of characters printed (not includes the trailing '\0' used to end output to strings).

example program

#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h> /* memset */

//  gcc -o fprintf_prg fprintf_prg.c
// ./fprintf_prg
int main () 
{
	printf("started program %s-%d\n", __FUNCTION__, __LINE__);
	
	FILE * filePointer;

	filePointer = fopen ( "filename.txt", "w+");
	fprintf( filePointer, "%s | (%s|%s|%d)", "data writing to file", __FILE__, __FUNCTION__, __LINE__);

	fclose( filePointer);

	return EXIT_SUCCESS;
}

output

filename.txt - file contains
data writing to file | (fprintf_prg.c|main|15)