Header File 

dir.h  

Category 

Directory Control Routines 

Prototype 

char *_mktemp(char *template); 

wchar_t *_wmktemp(wchar_t *template); 

Description 

Makes a unique file name. 

_mktemp replaces the string pointed to by template with a unique file name and returns template. 

template should be a null-terminated string with six trailing Xs. These Xs are replaced with a unique collection of letters plus a period, so that there are two letters, a period, and three suffix letters in the new file name. 

Starting with AA.AAA, the new file name is assigned by looking up the name on the disk and avoiding pre-existing names of the same format. 

Return Value 

If a unique name can be created and template is well formed, _mktemp returns the address of the template string. Otherwise, it returns null. 

Example  

#include <dir.h>
#include <stdio.h>
int main(void)
{
    /* fname defines the template for the
      temporary file.  */
    char *fname = "TXXXXXX", *ptr;
    ptr = mktemp(fname);
    printf("%s\n",ptr);
    return 0;
}

Portability