On Tue, 2005-06-28 at 22:52, fbsd_user wrote: > My sh shell script ability is not that good. > Have 2 simple coding problems. > > How do I code a statement to subtract one from a field. > > $rulenum = $rulenum - 1 > $rulenum = '$rulenum - 1' > > one='1' > $rulenum = $rulenum - $one > $rulenum='$rulenum - $one' > > None of that works. must really be simple. > > I also have this line > inruleno=`ipfw list | sed -n -e "s/00\([0-9]*\) $inblock/\1/p"` > > This works ok, the search argument is s/00\ but that is not good enough > because the number can be 0 to 65535. The sed -n -e "s/00\([0-9]*\ needs to > be changed to just return the first word. > > > Thanks for any help you can give. > > > _______________________________________________ > [email protected] mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "[EMAIL PROTECTED]"
"man expr" to give the short answer to your first question: As an example, x=`expr $x + 1` 536 ~ $ x=4 537 ~ $ x=`expr $x + 1` 538 ~ $ echo $ Note the back-quotes to execute a command and return the result, and the need for spaces between each token in the expr command. _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
