Fork & execl - System Software Lab - Program 9

Program for Fork:

#include stdio.h

#include stdlib.h

#include unistd.h

#include sys/types.h

int main(void)

{

        pid_t pid;

          char cwdir_cld[100];

          char cwdir_prt[100];

          if ((pid = fork()) < 0)

      {

                  perror("\nfork error : Cannot Create Fork\n");

                     exit(1);

          }

          if (pid == 0)

      {

                printf("\nInside child process\n");

/*   Now we are in the childs thread let us issue a chdir syscall :)     */

                  if(chdir("/tmp") < 0) {

                          perror("chdir error");

                   }

/*  Let us now print the current working directory of the child   */

                   if (getcwd(cwdir_cld, 100) != NULL) {

printf("\nCurrent working directory of the child is : %s\n", cwdir_cld);

                   } else {

                           perror("getcwd error");

                   }

             printf("\n End of Child Process\n");

                  

           /* end of the child */

          }

        else

      {

               printf("\n Inside Parent Process \n");

/* Now we are in the parent thread Let us check the current working directory */

                  if (getcwd(cwdir_prt, 100) != NULL)

            {

printf("\nCurrent working directory of the parent is : %s\n", cwdir_prt);

                   } else

            {

                           perror("getcwd error");

                   }

          }

        printf("\nEnd of Fork Program\n");

          return(0);

}

Program for Execl :

#include

int main()

{

  execl("/bin/ls","/bin/ls","-r","-t","-l", (char *) 0);

}