Select Code to Download

second_program filename            # as a command line option
echo "filename" | second_program   # piped into its standard input

system "./second_program", $filename and die ... # pass it on the comm
+and line
                                                 # note, system needs 
+"and" for error checking

open my $fh, "| ./second_program"    or  die ... # via stdin
print $fh $filename;                             # (note, no comma on 
+this line)