How to get the PID of a process by giving the process name in Mac OS X ?
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I am writing a script to monitor the CPU and MEM of any given process. For that i need to send in the name of the process to be monitored as a commandline argument. For example. 

    ./monitorscript <pname>

I need to get the pid of the process in the script so that i can use a `ps -p <pid>` inside. 

How do i get the pid of a process given its process name? 

I understand that there might be multiple processes in the same name. I just want to get the first process out of that list. 

