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how to create multiple child process and make parent process wait till all child procesas have exitted

Code:

if(fork()==0)

..

else if(fork()==0)

........

...............

.................

else wait();

doesnt work

Code:

int pids[27];

int i=0;

for(i=0;i<27;i++) {

  if((pids[i]=fork())!=0) {

  } else {

    printf("Hi, I'm child number %d\n", i);

    break;

  }

}

// Now the parent has started 27 childs.

// At this point, i contains values 0..27, inclusive. 0-26 with the childs

// 27 is the parent.

switch(i) {

  case 0: ....

    ... //Whatever the childs do..

  case 26: 

  case 27:

    { int j;    

      for(j=0;j<27;j++) waitpid(pids[i],NULL,0);

    }

}

Hi,
This is one way I could think of -

Code:

#include <stdio.h>

#include <pthread.h>

#include <stdio.h>

#include <stdio.h>

#include <sys/mman.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <signal.h>

#include <unistd.h>







pid_t pid;





pthread_t t1, t2;



void *

workthread (void *arg)

{

  pid = fork ();



  if (pid == 0)

    {

      fprintf (stderr, "\nchild pid : %d  and it's parent is %d\n", getpid (),

              getppid ());

      sleep (5);

    }

}



int

main ()

{

  int i = 0;



  for (i = 0; i < 5; ++i)

    {

      pthread_create (&t2, NULL, &workthread, NULL);

    }

  for (i = 0; i < 5; ++i)

    {

      pid = wait (NULL);

      fprintf (stderr, "\nchild %d terminated", pid);

    }

  return 0;

}

The code can be changed a bit if you want every child to perform different functions.