can regular perl program have multiple sub working at sametime?

Sure can: 

use threads;

async{
    print "I'm doing this over here while he's...", sleep 1 while 1 
}; 
print "doing that over there, while...", sleep 1 while 1;

I'm doing this over here while he's... 1.001
doing that over there, while... 1.001
I'm doing this over here while he's... 0.999772
doing that over there, while... 0.999429
I'm doing this over here while he's... 0.999626
doing that over there, while... 0.99956
I'm doing this over here while he's... 0.999724
doing that over there, while... 0.999355
Terminating on signal SIGINT(2)

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In reply to Re^4: using system and exec in same script using child by BrowserUk
in thread using system and exec in same script using child by convenientstore

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