fork() & execvp() UNIX System Call

#include  <stdio.h>

#include  <stdlib.h>

#include  <sys/types.h>

int spawn (char* program, char** arg_list)

{

  pid_t child_pid;

  child_pid = fork ();

  if (child_pid != 0)

          return child_pid;

  else {

     execvp (program, arg_list);    

     fprintf (stderr,"an error occurred in execvp\n");

     abort ();

  }

}

int main ()

{

   char* arg_list[] = { "ls", "-l", "/", NULL  };

   spawn ("ls", arg_list);

  printf ("done with main program\n");

  return 0;

 }

Output:

  

[telnet17@linux ~]$  ./a.out

done with main program

[telnet17@linux ~]$ total 138

drwxr-xr-x   2 root root  4096 Sep 12  2009 bin

drwxr-xr-x   4 root root  1024 Sep 12  2009 boot

drwxr-xr-x  11 root root  3620 Mar 16 19:16 dev

drwxr-xr-x  93 root root 12288 Mar 16 19:16 etc

drwxr-xr-x 115 root root  4096 Feb  9 20:26 home

drwxr-xr-x  14 root root  4096 Sep 12  2009 lib

drwx------   2 root root 16384 Sep 12  2009 lost+found

drwxr-xr-x   2 root root  4096 Sep 12  2009 media

drwxr-xr-x   2 root root     0 Mar 16 19:16 misc

drwxr-xr-x   2 root root  4096 Oct 11  2006 mnt

drwxr-xr-x   2 root root     0 Mar 16 19:16 net

drwxr-xr-x   2 root root  4096 Oct 11  2006 opt