On 22/08/14 18:02, Sven Hartge wrote: > Tony van der Hoff <t...@vanderhoff.org> wrote: >> On 22/08/14 15:57, Sven Hartge wrote: >>> Tony van der Hoff <t...@vanderhoff.org> wrote: >>> >>>> Cron task is invoked from a simple crontab entry: >>>> # /home/tony/crontab -- crontab for user tony >>>> MAILTO=t...@vanderhoff.org >>>> SHELL=/bin/sh >>>> <snip> >>>> * * * * * /home/tony/scripts/test >>> >>>> tony@tony-fr:~$ ls -al /dev/stdout >>>> lrwxrwxrwx 1 root root 15 Aug 21 17:30 /dev/stdout -> /proc/self/fd/1 >>> >>>> tony@tony-fr:~$ ls -ald /dev >>>> drwxr-xr-x 15 root root 3340 Aug 21 17:30 /dev >>> >>> At least you don't have a multi-gigabyte /dev/stdout-file on your system >>> filled with the output of numerous scripts from years ago :) >>> >>> I'd guess /proc/self/fd/1 is different for programs invoked from cron, >>> because cron redirects stdout to catch any output from programs. >>> >> Well, indeed. The output from cron scripts normally goes to mail in this >> case. I'm rather hoping that is where the output from stdout would go. > > If you want to have an output which is selectable between debug and > no-debug output it would be better to write a small shell function and > use that instead of "echo" to print things. Much more flexible, you can > even easily add a timestamp on front of every messagen etc. > >>> Please add something like this: >>> >>> ls -al /proc/self/fd/1 /dev/stdout 2>&1 > /tmp/testoutput >>> >>> to your script and provide the output. Maybe this will be helpful. >>> >> lrwxrwxrwx 1 root root 15 Aug 21 17:30 /dev/stdout -> /proc/self/fd/1 >> l-wx------ 1 tony tony 64 Aug 22 16:39 /proc/self/fd/1 -> /tmp/testoutput > >> Not sure how that helps :( > > No, but this was my fault. "/proc/self/fd/1" is magic, it always points > to the stdout of current program. If you redirect it, like I asked you > to do, then of course /proc/self/fd/1 points to the new target. > > So please only use "ls -al /proc/self/fd/1 /dev/stdout" and paste the > output from the mail you get. >
Thanks Sven. FWIW that yields: lrwxrwxrwx 1 root root 15 Aug 21 17:30 /dev/stdout -> /proc/self/fd/1 lrwx------ 1 tony tony 64 Aug 23 10:35 /proc/self/fd/1 -> /tmp/tmpfVNGK0G (deleted) However, from reading Karl Jorgensen's post, I now think I understand what's happening, and I can't explicitly send stuff to stdout from a cron script. Ah, well... Thanks for your help. -- Tony van der Hoff | mailto:t...@vanderhoff.org Ariège, France | -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/53f8575c.3050...@vanderhoff.org
