/*  vulp.c  */

    #include <stdio.h>
    #include<unistd.h>

    #define DELAY 10000

    int main()
    {
       char * fn = "/tmp/XYZ";
       char buffer[60];
       FILE *fp;
       long int  i;

       /* get user input */
       scanf("%50s", buffer );

       if(!access(fn, W_OK)){
           /* simulating delay */
            for (i=0; i < DELAY; i++){
               int a = i^2; 
            }

            fp = fopen(fn, "a+");
            fwrite("\n", sizeof(char), 1, fp);
            fwrite(buffer, sizeof(char), strlen(buffer), fp);
            fclose(fp);
       }
       else printf("No permission \n");
    }