6 prepend_file() -- prepend text to the front of a file
8 options: lock file? enable atomic
10 edit_file() -- slurp into $_, call edit code block, write out $_
14 edit_file_lines() -- slurp each line into $_, call edit code block,
20 reads lines to array ref or list
21 same as $list = read_file( $file, { array_ref => 1 }
22 or @lines = read_file()
24 new options for read_dir
25 prepend -- prepend the dir name to each dir entry.
26 filter -- grep dir entries with qr// or code ref.
30 restart sysread/write after a signal (or check i/o count)