We generally used to check a process is alive by some methods.

on *nix systems
'top' command or ps command output
kill -0 pid
heart beats, this method will check the process is functional apart from alive status, heart beats are simple messages(usually program name+timestamp) will be sent to heart beat monitoring(hbm) server through socket, and the duty of the hbm server is to restart that process if no heart beats received for a configured amount of time.
hope this helps

Vivek
-- In accordance with the prarabdha of each, the One whose function it is to ordain makes each to act. What will not happen will never happen, whatever effort one may put forth. And what will happen will not fail to happen, however much one may seek to prevent it. This is certain. The part of wisdom therefore is to stay quiet.

In reply to Re: monitor process by targetsmart
in thread monitor process by grashoper

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