Thanks! And thanks for the links.
(One can never read the bash man page carefully enough...)
On 11/17/20 12:00 PM, Moshe M. Katz wrote:
> `$-` means the options in your current shell.
>
> * `h` = hashall
> * `i` = interactive
> * `m` = monitor
> * `B` = braceexpand
> * `C` = noclobber
> * `H` = histexpand
>
> `${-#*i}` means:
>
> * `-` = Take the shell options
> * `#` = remove the leading match from the parameter
> * `*i` = the pattern to search for
>
> So this takes the string "himBCH", finds the prefix "hi", and removes it.
>
> It looks like the goal is to only do these operations if the script is
> running non-interactively, such as in a cron job, since I assume the
> letters are always in the same order.
>
> Useful bash resources for this kind of thing:
>
> *
> https://www.gnu.org/software/bash/manual/html_node/Shell-Parameter-Expansion.html
> * https://www.gnu.org/software/bash/manual/html_node/Pattern-Matching.html
> * https://tldp.org/LDP/abs/html/options.html
>
>
> Moshe
>
> --
> Moshe Katz
> mmk...@umd.edu <mailto:mmk...@umd.edu>
> (301) 867-3732
>
> <http://stackexchange.com/users/440421>
>
>
> On Tue, Nov 17, 2020 at 9:05 AM Judah Milgram <milg...@cgpp.com
> <mailto:milg...@cgpp.com>> wrote:
>
> I mean: for i in file1 file2...
> (not f)
>
>
> On 11/17/20 9:00 AM, Judah Milgram wrote:
> > I've combed the man page to the best of my ability and can't
> figure out
> > this snippet from a bash script:
> >
> > for f in file1 file2.... do
> > if [ "${-#*i}" = "$-" ]; then do stuff...
> > done
> >
> > What are those two expansions? They expand consistently to mBCH and
> > himBCH which rings a bell somewhere but my lockdown-addled brain just
> > can't place it.
> >
> > thanks...
> > Judah
> >
> >
>
>
> --
> Judah Milgram
> milg...@cgpp.com <mailto:milg...@cgpp.com>
> 301-257-7069
>
> You received this email because you are subscribed to the UM Linux
> User's Group (UM-LINUX) mailing list. If you would like to
> unsubscribe from this list, simply send an email to
> lists...@listserv.umd.edu <mailto:lists...@listserv.umd.edu> with
> the message signoff UM-LINUX in the body.
>
> You received this email because you are subscribed to the UM Linux
> User's Group (UM-LINUX) mailing list. If you would like to unsubscribe
> from this list, simply send an email to lists...@listserv.umd.edu with
> the message signoff UM-LINUX in the body.
--
Judah Milgram
milg...@cgpp.com
301-257-7069
You received this email because you are subscribed to the UM Linux User's Group
(UM-LINUX) mailing list. If you would like to unsubscribe from this list,
simply send an email to lists...@listserv.umd.edu with the message signoff
UM-LINUX in the body.
