This is very easy to do using threads.

#! perl -slw
use strict;
use threads;

my( @t, @r );

push @t, async { `dir /s c:` };
push @t, async { `dir /s d:` };
push @t, async { `dir /s p:` };

print "doing other stuff..." for 1 .. 10;

# get and print the results.
push @r, $_->join for @t;
print for @r;
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