HI ALL,

I have a small question to all really great linux users and administrators. i couldn't understand the following program. can u please explain in short and in easy way. The program is
------------------------------------------------------------------
#include <sys/wait.h>

#define NULL 0

int main (void)
{
if (fork() == 0){ /* This is the child process */
execve("child",NULL,NULL);
/*
execvp("./Child",NULL);
exit(0);
*/
//printf("I am child process\n");
//exit(0);
}

/* Parent code here */
printf("Process[%d]: Parent in execution ...\n", getpid());
sleep(5);
if(wait(NULL) > 0) /* Child terminating */
printf("Process[%d]: Parent detects terminating child \n", getpid());
printf("Process[%d]: Parent terminating ...\n", getppid());

}
------------------------------------------------------------------------
where i did not understand is

1) what is execve("child",NULL,NULL);
2)from --> Sleep(5) TO THE END,I DID NOT UNDERSTAND.
Can anybody help me please. its not tough for u greats but if u explain me,i would be more than blessed. Thanks.

Looks like a pretty simple homework exercise to me.

It has something to do with forking and process id's .. Why don't you just try the script and see what it does.

Use better thread titles.

palisetty;

You did not follow up in your last homework thread-----here:
http://www.linuxquestions.org/questi...9/#post3412997

Giving both threads the same (un-helpful) title was not a good move either.

You CAN get help with homework here, but not like this.......

As for the substance, two questions:

1. Do you know what the code is supposed to do?

2. Where is the function "execve" defined? Do you think that definition might help you understand what is happening?

A couple of things.

First, as Nylex stated, Please use better thread titles than "Please Help". There should be something relating to the thread topic, in this case something like "query with routine in small program - HOMEWORK"

Second, when posting code please enclose it with the CODE tags (by clicking on the # symbol on the Post Thread/Reply to Thread dialogue box) this makes it so much easier to read as it keeps the formating.

Third, please state what you have tried already (including google searches)

These links should help you understand better:

sleep()
http://osr507doc.sco.com/en/man/html.C/sleep.C.html

execve()
http://www.cs.ui.ac.id/WebKuliah/IKI...ng_a_File.html

wait()
http://docsrv.sco.com:507/en/man/html.C/wait.C.html

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