perl -MIPC::Run=run -e '
run( [ "perl", "timestamp.pl" ],
       "1>", sub { print "out " . time() . " " , @_ },
       "2>", sub { print "err ". time() . " " , @_} )
'
out 1215247029 1215247029 info
err 1215247029 1215247029 warn
err 1215247029 1215247029 warn
out 1215247029 1215247029 info
err 1215247029 1215247029 warn
err 1215247029 1215247029 warn
out 1215247030 1215247030 info
err 1215247030 1215247030 warn
err 1215247030 1215247030 warn
err 1215247030 1215247030 warn
err 1215247030 1215247030 warn
out 1215247030 1215247030 info
err 1215247030 1215247030 warn
out 1215247030 1215247030 info
out 1215247030 1215247030 info
out 1215247031 1215247030 info
out 1215247031 1215247031 info
err 1215247031 1215247031 warn
err 1215247031 1215247031 warn
out 1215247031 1215247031 info
err 1215247031 1215247031 warn
out 1215247031 1215247031 info
out 1215247031 1215247031 info
err 1215247031 1215247031 warn
err 1215247031 1215247031 warn