Hello, I have a grep expression using cygwin grep on Win. grep -a "\\,,/\|\\m/\|\\m/\\>\.</\\m/\|:u" all_fbs.txt > rockon_fbs.txt Once I identify the emoticon class, however, I want to strip them out of the data. However, the same regexp above within a sed results in a syntax error (yes, I realize I could use /d instead of //g, but this doesn't make a difference, I still get the error.) sed "s/\(\\,,/\|\\m/\|\\m/\\>\.</\\m/\|:u\)*//g" The full line is: grep -a "\\,,/\|\\m/\|\\m/\\>\.</\\m/\|:u" all_fbs.txt | sed "s/\(\\,,/\|\\m/\|\\m/\\>\.</\\m/\|:u\)*//g" | sed "s/^/ROCKON\t/" > rockon_fbs.txt The result is: sed: -e expression #1, char 14: unknown option to `s' I know it's coming from the sed regexp I'm asking about it b/c if I remove that portion of the full line, then I get no error (but, of course, the emoticons are not filtered out). Thanks in advance, Steve