#include <sys/types.h>
#include <stdio.h>
#include<unistd.h>

int main()
{
  pit_t pid;

  /* for a child process */
  pid = fork();

  if ( pid < 0 ) { /* fork failed */
    fprintf( stderr, "Fork failed" );
    exit( -1 );
  }
  else if ( pid == 0 ) { /* This is child process */
    execlp( "/bin/ls", "ls", NULL );
  }
  else { /* this is parent process */
    wait( NULL );
    printf( "child complete" );
    exit( 0 );
  }
}