use IPC::Open2;
use File::Temp;
my ($fh, $path) = tempfile();
unlink($path);   # automatically releases storage on exit
my $pid = open2($fh, \*STDIN, ’some', 'cmd', 'and', 'args');
waitpid $pid, 0; # wait for child to exit

# now you can read the child's output from $fh