Is that a typo? Replace 
exec `some unix command`;

[download]
with 
exec 'some unix command';

[download]
You probably don't want to exec a command line that was printed by some other command. The backticks (see perldoc perlop about qx) collect output from a command, while exec takes a string argument.

--
[ e d @ h a l l e y . c c ]

In reply to Re: how to run a process in background mode by halley
in thread how to run a process in background mode by w3ntp

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