STDOUT/STDERR/cron trivia

[Adam Garsha]

I get an Email from cron each night because a cron entry's stdout is not being properly redirected to a log file or bit-bucket.


logout


*************************************************
Cron: The previous message is the standard output
and standard error of one of your crontab commands:

. /etc/profile 1>/dev/null 2>&1; /optim/bin/sel_efta_priv -p1 -p5 -p9 -sy 1>/dev/null 2>&1 #Turn on statements for privileges



As you can see, streams 1 and 2 are being directed to /dev/null in the cron entry. Any ideas about why the "logout" is making its way through to STDOUT or STDERR?

I think the answer lies in the ".", but I can't remember the specifics on what this does in the shell. Isn't it "run the following in the current shell process"?

Thanks in advance.

[Steven E. Protter]

the cron command seems a little complex.

If this worked previously, what has changed recently?

SEP

[RAC_1 · Accepted solution]

It is coming from /etc/profile. you seem to have a trap statement somewhere in the cron script. That is echoing it.

[Adam Garsha]

To Steve:

It still works fine; I have just started trimming down all the root Email that I get (from multiple hosts) and this message has been one that I haven't had time to look into before now... hence, the post.

[Pete Randall]

I have the same problem with one of my cron jobs. It also sources /etc/profile. As I recall, it's the

"trap "echo 'logout'" 0"

line that causes this. I tried removing it and that caused other problems with /etc/profile so I decided to just live with it.


Pete

[Adam Garsha]

Yes, it is /etc/profile and it is that trap line. I looked at a few hosts and that looks like it is standard for HP-UX. Any ideas why? What is the value of that line?

What kind of problems happen when the line is removed?

[RAC_1]

What that lines does is, it echos logout when it catches signal 0. when you logout, it echoes "logout"

You can take it out.

Anil

[Pete Randall]

Adam,

Sorry, I don't recall why I decided to live with it, but a little research into the trap command led me to this little tidbit:

root# trap
trap -- 'echo '\''logout root'\' EXIT
root#

The trap seems to still be in effect, but only for root:

$ trap
$

That leads me to believe that it was OK for regular users but caused problems for root?


Pete