Text replacement

I need something that will take something from a text file, replace text in it, then export a new file.

Can someone please help me out?

>>9
[m][08:03]    <TuringTest>    I am tracking down a regex bug from OS X to see if it is in the FreeBSD derived code. Could someone on *BSD check what the following command prints: echo "ab" | sed -E "s/(()|.)(b)/[&]/"
[08:03]    <TuringTest>    For comparison the other order in the regex is : echo "ab" | sed -E "s/(.|())(b)/[&]/"
[08:04]    <TuringTest>    They SHOULD agree, but I am seeing a difference
[08:04]    <methi>    first gives "a[b]" second "[ab]"[/m]
OH SHI-