Create a unique temporary filename.

This function is compatible with the following targets:

ANSI

BeOS

EMB/RTOS

Mac OS

Palm OS

Win32

#include <stdio.h>

char *tmpnam(char *s);

Parameters for this facility are:

s

char *

A temporary file name

The tmpnam() functions creates a valid filename character string that will not conflict with any existing filename. A program can call the function up to TMP_MAX times before exhausting the unique filenames tmpnam() generates. The TMP_MAX macro is defined in stdio.h.

The s argument can either be a null pointer or pointer to a character array. The character array must be at least L_tmpnam characters long. The new temporary filename is placed in this array. The L_tmpnam macro is defined in stdio.h.

If s is NULL, tmpnam() returns with a pointer to an internal static object that can be modified by the calling program.

Unlike tmpfile(), a file created using a filename generated by the tmpnam() function is not automatically removed when it is closed.

tmpnam() returns a pointer to a character array containing a unique, non-conflicting filename. If s is a null pointer (NULL), the pointer refers to an internal static object. If s points to a character array, tmpnam() returns the same pointer.

"fopen"

"tmpfile"

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
	FILE *f;
	char *tempname;
	int c;

	// get a unique filename
	tempname = tmpnam("tempwerks");

	// create a new file for output
	if ( (f = fopen(tempname, "w")) == NULL) {
		printf("Can't open temporary file %s.\n", tempname);
		exit(1);
	}

	// output text to the file
	fprintf(f, "shoe shirt tie trousers\n");
	fprintf(f, "province\n");
	
	// close the file
	fclose(f);

	// delete the file	
	remove(tempname);

	return 0;
}