File loging

[hpuxrox]

Hi,

I am looking for a way to log stdin and stderr inline from within a script and send the information to logfile and terminal without the use of the "tee" command.

ex:

exec 2>&1 1> logfile.log

[James R. Ferguson]

Hi:

#!/usr/bin/sh
exec 1> /tmp/mylog
exec 2>&1
echo "stdout to log..."
print -u2 "stderr to log, too"

Regards!

...JRF...

[Jeff_Traigle]

You can't. That's why tee exists.

[hpuxrox]

Ok, it I must use tee how would I do that inline?

[A. Clay Stephenson]

You were already very close:

ls 2>&1 | tee /var/tmp/outfile

[Court Campbell]

exec 2>&1 | tee logfile.log

[Jeff_Traigle]

your command | tee -a logfile

See the tee(1) man page. (There's not much more to it than that.

You can send the stdout and stderr to the log for the entire script as follows:

#!/usr/bin/sh
(
your command in here
) | tee -a logfile

The parentheses start a subshell from which all stdout and stderr is piped to the tee command. Much easier than adding the tee command to every command that generates output in the script.

[hpuxrox]

by inline, I mean from within the script, not from one line.

#!/usr/bin/sh
exec 1> /tmp/mylog
exec 2>&1
echo "stdout to log..."
print -u2 "stderr to log, too"

basically the above but needs to go to the terminal too..

[Court Campbell]

You might try:

#!/usr/bin/sh
exec 1> /tmp/mylog | tee /dev/console
exec 2>&1
echo "stdout to log..."
print -u2 "stderr to log, too"

[A. Clay Stephenson]

Okay, I thought you would be able to take it from the point that I left it, but ...

Create a file my.sh:
----------------------------------
#!/usr/bin/sh

exec 2>&1
some_command
echo "Test Stuff"
some_opther_command
exit 0
-----------------------------------

Now when you invoke my.sh from an interactive shell or from a wrapper shell:

my.sh | tee /var/tmp/outfile

All stderr and stdout from my.sh will de directed to both the controlling terminal and to /var/tmp/outfile.

[hpuxrox]

Thanks clay, but all must be in one script. I can not have sub-scripts. Don't ask me why.. long story.

[Peter Nikitka]

Hi,

I hope you can call your script more than once:

#!/usr/bin/ksh
if [ -z "$MY_SCRIPT_WRAPPER" ]
then
export MY_SCRIPT_WRAPPER=1
exec $0 2>&1 | tee /tmp/logfile
exit 0
fi

# original code here

mfG Peter

[hpuxrox]

After hacking around, I came up with this,

#!/usr/bin/sh
NAMEDPIPE=/tmp/TDL.pipefile
mkfifo ${NAMEDPIPE}
cat ${NAMEDPIPE} | tee sample.log &
exec 1> ${NAMEDPIPE}
exec 2>&1


#Main Script
ps -ef
print -u2 "stderr to log, too"

Seems to work, anyone have any better ways?

[A. Clay Stephenson]

Here's another approach:

Have your script build a script "on the fly" either with echo's or a heredoc section and then invoke the built script and have a trap to remove the temp script file on exit. This meet's your requirement of having it all in one script. This is a common technique for doing complex operations in the shell or if you have to build awk scripts on the fly and then invoke them.

[Peter Nikitka]

Hi,

I would append something unique to the name of the pipe like
NAMEDPIPE=/tmp/TDL.pipefile.$$

Multiple instances of your script running at the same time would cause trouble otherwise.

Removing the temporary FIFO after the run of the script will prevent potential permission problems, when at later times an existing FIFO created by another user is found at runtime.

mfG Peter