with gnu awk (`gawk`) you can use some zero-length assertions like `\<` or `\>`:
$ echo 'a\ b c' | gawk 'BEGIN{FS="\\> +"} {print $1}'
a\ b
but unfortunately not the full-blown ones from `perl` or `pcre` (eg. `(?
$ echo 'a\ b, c' | perl -nle '@a=split /(? a\ b,