For example, if I want to monitor a process which will execute another process with specified arguments, how can I get that?
Mac OS X System Monitor and Process Explorer Tool
atMonitor is an advanced monitoring tool for Mac OS X that displays system activity in real-time. It is designed to allow quick assessment of computer's state and it is powerful enough to make it a core utility in anyone's system troubleshooting toolkit. atMonitor offers a better alternative to Apple's own "Activity Monitor" and combines the best of the features of many other existing monitoring utilities. It also adds an extensive list of unique features of its own. In addition to the standard CPU, Disk and Network info, atMonitor allows interaction with processes, setting up triggers, logging, purging RAM and much more. atMonitor can be displayed in the menu bar, as a stand alone floating window or in the dock icon. The last version of atMonitor to support GPU related features is atMonitor 2.7.1. The last version of atMonitor to support PPC is atMonitor 2.1.5, which is no longer supported, but available for those with PPC based Macs.
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