Thread: Double Fork Problem

I am having problems with running a child in the background. I want the child to run and then keep the parent active.

This is what keeps happening:
PID TTY TIME CMD
16844 pts/0 00:00:00 bash
5262 pts/0 00:00:00 youare
5263 pts/0 00:00:00 youare <defunct>
5264 pts/0 00:00:00 ps

youare is my main program and it keeps getting defunct.

Here is the section of my code that is doing the forking and executing:

Code:

pid_t childPid;
pid_t pid;
int status;


if ((childPid = fork()) == 0) //1st child
    {
      
      
    if ((pid = fork()) != 0) // 2nd child
      {
        exit(0);
      }
      
    
    if (execlp ("ps", "ps", (char *)0) == -1)
     {
       perror("exec");
       exit(0);
     }

    }
}

Thank you!

I don't think my question was answered correctly. I don't want to wait because I want the program to run in the background, in this case the ps command. While it's running in the background I want to be able to still control my main program.

Here is an updated version of my excerpt of my program.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <fcntl.h>
#include <time.h>
#include <sys/param.h>
#include <signal.h>


main()
{
pid_t childPid;
pid_t pid;
int status;
char test[100];


while(1)
{
  printf("%> ");
  scanf("%s", &test);
  if (strcmp(test,"go") ==0)
  {

    if ((childPid = fork()) == 0) 
    {
      
      
      if ((pid = fork()) != 0)
      {
        exit(0);
      }
      
    
    if (execlp ("ps", "ps", (char *)0) == -1)
    {
      perror("exec");
      exit(0);
    }
        
   }
  }
  else if (strcmp(test,"exit") ==0)
   exit(0);

}

}

Thank you!