Hi Mikael, one simple way to do it: result: make block! 100 remove-these: [ "get rid of this" "remove this" ] foreach line read/lines %test.txt [ foreach pattern remove-these [ if found? find line pattern [clear line] ] if > length? line 0 [append/only result line] ] Note that this implementation wil skip empty lines in the log file! Using this example file - test.txt: This is line 1 remove this this is line 2 this is line 3 this is line 4 remove this this is line 5 get rid of this this is line 6 this is line 7 this is line 8 get rid of this this is line 9 this is line 10 remove this We get the following results: >> foreach line result [print line] this is line 2 this is line 3 this is line 6 this is line 7 this is line 9 At 02:33 AM 11/29/99 +0100, you wrote: >I've just started out with some REBOL programming and the first task I was >planning to solve is this: > >I got a backup log that I want to filter out all rows that match a set of >strings. > >1. Open a text file >2. Compare every line with all strings. And if match delete row. >3. Write file back to disk. > >I've got a little bit of code doing this with one match string today :-) But >I'm not going to show you how I did :-) Ugly code... I believe. > >Thanks :-) > >-- > Mikael Östergren > [EMAIL PROTECTED] > mob: +46 (70) 555 4431 > fax: +46 (8) 5981 5932 > voice box: +46 (8) 5981 5932 > > >