/* illustrates how a system command is generated and excuted by a C program */
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

#define	MAXSTRING	100

main()
{
  char command[MAXSTRING], *tmp_file_name;
  int c;
  FILE *ifp;

  tmp_file_name = tmpnam(NULL); /* creates temporary file name */
  sprintf(command, "dir > %s", tmp_file_name);
  printf("Compiled command is %s \n\n", command);
  system(command);
  ifp = fopen(tmp_file_name, "r");
  while ((c = getc(ifp)) != EOF)
	putchar(tolower(c));
  remove(tmp_file_name);
}