On 22 May 2014 14:12, <li...@sbt.net.au> wrote: > On Wed, May 21, 2014 12:28 pm, pe...@chubb.wattle.id.au wrote: > > > As you're not using regular expressions, but just strings, fgrep is > > the way to do it. fgrep -q '07/2014 15/06/2014 > > 20/06/2014 > > 25/06/2014' part 2 && exit 0 > > Peter, thanks > > Amos, you've per-emptied my next Q, thanks >
Glad I did :) > > I actually should move it totally out of script, as this list will often > change, so (I think?) I can enter dates into a file, say 'patterns' > > and, use like > > fgrep -q -f /path/to/pattern part2 && exit 0 > Yes this will work. One pattern per line. See "man grep". No need to quote or anything since it's not parsed through the shell. > > ? > > will I need any quotes in file 'pattern', or simply like: > > 07/2014 > 15/06/2014 > 20/06/2014 > 25/06/2014 > > thanks again > > V > > > On Wed, May 21, 2014 7:24 pm, Amos Shapira wrote: > > It might be more maintainable to keep the list of patterns in a variable > > (line per pattern) then pass it to grep using grep's -f/--file= argument: > > > > > > PATTERNS="15/06/2014 > > 20/06/2014 > > 25/06/2014" > > > > > > ... > > grep -q -f <(echo "$PATTERNS") file2 && exit 0 > > > > Note the use of double quotes around the variable interpolation in the > > grep command line, they are essential to preserve the newlines in the > > variable's value. > > > > The (bash specific, I think) trick here if the use of "<(command)" which > > causes bash to open a pipe to the command and pass its name as > > /dev/fd/FILE-DESC-NUMBER to grep so grep thinks it's a regular file to > > read match patterns from while its stdin is still free to read the input > > to match against the patterns. If grep doesn't read its input from stdin > > but from a regular file then you don't need this trick and can just pass > > "-f -" > > to make grep read the patterns from stdin and the matching text from the > > regular file: > > > > grep -q -f - file2 && exit 0 <<<"$PATTERNS" > > > > (actually this uses another bash specific trick, you can do the following > > to get rid of bash'ism completely: > > > > echo "$PATTERN" | grep -q -f files && exit 0 ) > > > -- > SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ > Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html > -- [image: View my profile on LinkedIn] <http://www.linkedin.com/in/gliderflyer> -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
