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

int main(int argc, char *argv[])
{

  FILE *fd;

// Allocating memory on the heap
  char *userinput = malloc(20);
  char *outputfile = malloc(20);

if(argc < 2)
{
  printf("Usage: %s <string to be written to /tmp/notes>\n", argv[0]);
  exit(0);
}

// Copy data into heap memory
  strcpy(outputfile, "/tmp/notes");
  strcpy(userinput, argv[1]);

// Print out some debug messages
  printf("---DEBUG--\n");
  printf("[*] userinput  @ %p: %s\n", userinput, userinput);
  printf("[*] outputfile @ %p: %s\n", outputfile, outputfile);
  printf("[*] distance between: %d\n", outputfile - userinput);
  printf("----------\n\n");

// Writing the data out to the file.
  printf("Writing to \"%s\" to the end of %s...\n", userinput, outputfile);

  fd = fopen(outputfile, "a");
  if (fd == NULL)
  {
    fprintf(stderr, "error opening %s\n", outputfile);
    exit(1);
  }

  fprintf(fd, "%s\n", userinput);
  fclose(fd);

  return 0;
}