One of the following "forking opens" might suit your needs 

my $pid = open my $fhOut, "| the command ", or die ...;

## or
my $pid = open my $fhIn, "the command |", or die ...;

## or using the 3-arg form on *nix systems
my $pid = open my $fhOut, '|-', "the command ", or die ...;

## or 
my $pid = open my $fhIn, '-|', "the command", or die ...;

[download]

Or list forms of the latter two, if you need to pass arguments, may make sense on your system.

See open and perlopentut for more information.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In reply to Re: Executing a process in the background AND getting its pid by BrowserUk
in thread Executing a process in the background AND getting its pid by henrikbe

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