Re: crontab problem with stdout

On 2007-11-21 02:59, root wrote:
I am getting screwed up trying to get around the problems with
stdout using cron. What I want to do is periodically fetch
a formatted web page, process that, and send the result
to a file. I use w3m to format the page:

w3m -dump http://somepage

First I tried processing that via a pipe:

w3m -dump http://somepage | process >>final.result

But the stdout for the input to the pipe gets lost.
...

Maybe you redirect stdout in your crontab entry.

Just try:
(w3m -dump http://somepage | process >>final.result) 2>> final.errors

But be nice when using cron for jobs that do remote things, and think what the
owner of http://somepage like if thousands of cronjobs should do the same at
the same time from unix/linux where the clock mostly is synced, and will generate a network storm.

Rules. Never do cron entries at minute 0 for remote access, and calculate with
the possible risk that a site don't respond, so if you run it more often then the timeout, you will mess up your output.

/bb
.

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