How to create Zombie ?

[alikhan707]

Hey guys i need help on this problem ....
Please tell me how to create zombie in linux using fork() ?

[ashitpro]

Hey guys i need help on this problem ....
Please tell me how to create zombie in linux using fork() ?

when parent process issues a fork system call, it spawns a child process.
Idly parent should query the exit status of the child process by system calls like waitpid,wait etc.
But if parent process fails to do this or never issues such calls and just get terminate, then child process is said to be zombie(other name is orphan) i.e process having no parent. It just exists in memory holding the resources.

int main()
{
     int pid;
     pid=fork();
     if(pid>0)//child
     {
           sleep(1000);
     }
     else//parent
     { 
           exit(0);
     }
}

[micmast]

Couldn't the above code be shorter?

like this:

int main() {
for(;;) {
fork();
}
}

[alikhan707]

Hey guys thanx for the replies :)
Next question, i want to ask is that how to solve these both zombie and orphan process problems ? Can u explain with an example ?
thanx...

[jrichard]

when parent process issues a fork system call, it spawns a child process.
Idly parent should query the exit status of the child process by system calls like waitpid,wait etc.
But if parent process fails to do this or never issues such calls and just get terminate, then child process is said to be zombie(other name is orphan) i.e process having no parent. It just exists in memory holding the resources.

int main()
{
     int pid;
     pid=fork();
     if(pid>0)//child
     {
           sleep(1000);
     }
     else//parent
     { 
           exit(0);
     }
}

I have a doubt is not zombie and orphan two different process? how do you link these both? Please explain me

[ashitpro]

I have a doubt is not zombie and orphan two different process? how do you link these both? Please explain me

Go through this link...
If you still have any doubts let us know...

http://wiki.answers.com/Q/What_is_Zombie_Process_and_Orphan_Process

[Subsciber123]

Zombies are processes that have terminated but whose return value has not been read by the parent. waitpid() collects return values and kills zombies.

Orphans are child processes whose parents have died. Orphans are supposed to be adopted by init (which has PID=1).