On 28Apr2010 20:23, Dave Ihnat <dihnat@xxxxxxxxxx> wrote: | On Thu, Apr 29, 2010 at 10:59:45AM +1000, Cameron Simpson wrote: | > Then it is excessive. Drop the "2>&1" and it should _still_ work. | > As mentioned earlier, this incantation is backwards. Redirections are | > applied left to right, so "2>&1" probably changes nothing. | | Hm. Actually, this is very common in Unix/Linux; it indicates | redirecting the error stream into the stdout stream. If the messages | are being generated on the stdout stream, you're right. The redirection indeed sends stderr to stdout. BUT... It _then_ sends stdout to a file, and _do_not_ take stderr with it. Usually what people want is both streams in the file, done like this: >filename 2>&1 "Send stdout to the file, send stderr to where stdout is now going." Thus both into the file. The redirection supplied: 2>&1 >filename sends stderr to wherever stdout _was_ going, then sends stdout to a file, leaving stderr _not_ going to the file but to stdout's old destination. It boggles my mind that I've seen three separate people recommend the latter usually-wrong ordering in this thread. Maybe you're all reading something into the OP's requirements that I missed? Observe: [/home/cameron]janus*255> cat >>foo.sh echo out >&1 echo err >&2 [/home/cameron]janus*> sh foo.sh out err [/home/cameron]janus*> sh foo.sh >out 2>&1 [/home/cameron]janus*> cat out out err [/home/cameron]janus*> sh foo.sh 2>&1 >out err [/home/cameron]janus*> cat out out [/home/cameron]janus*> Is this unexpected? Cheers, -- Cameron Simpson <cs@xxxxxxxxxx> DoD#743 http://www.cskk.ezoshosting.com/cs/ Draw little boxes with arrows. It helps. - Michael J. Eager -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
