topic Re: command | tee -a file in Operating System - Linux

command | tee -a file

Leo The Cat — Tue, 19 May 2009 13:13:23 GMT

Hi

Here my command:

java -jar example.jar | tee -a /tmp/aa.log
echo $?

The problem here is that $? is always 0, of course, because the last command is tee (not my java command). How to catch the return value code for java command ?

Bests regards
Den

Re: command | tee -a file

Ivan Ferreira — Tue, 19 May 2009 13:20:47 GMT

Maybe you should change to:

java -jar example.jar >> /tmp/aa.log 2>&1
echo $?

Re: command | tee -a file

Leo The Cat — Tue, 19 May 2009 13:22:08 GMT

Hi.

No I need the tee ....

Bests Regards
Den

Re: command | tee -a file

Ivan Ferreira — Tue, 19 May 2009 13:52:49 GMT

Then try using the PIPESTATUS variable:

java -jar example.jar | tee -a /tmp/aa.log
echo $PIPESTATUS

PIPESTATUS
An array variable (see Arrays below) containing a list of exit status values from the processes in the most recently-executed foreground pipeline (which may contain only a single command).

Re: command | tee -a file

Jared Middleton — Tue, 19 May 2009 22:41:09 GMT

Here are some examples I put together years ago...

UNIX RETURN CODE PRIMER
[tested on Red Hat Linux using bash-2.05]

In the examples below:
- it is assumed that you want to both display the output of the command (ls) and capture the exit code (a.k.a. return code value) in a variable (rc).
- a return code value other than "1" means the script did not work correctly.

# Basic (correct)
$ ls nonexistent 2>&1; rc=$?; echo $rc
ls: nonexistent: No such file or directory
1

# Capture return code after pipe (wrong)
$ ls nonexistent 2>&1 | tee -a /dev/null; rc=$?; echo $rc
ls: nonexistent: No such file or directory
0

# Capture return code after command (wrong)
$ ls nonexistent 2>&1; rc=$? | tee -a /dev/null; echo $rc
ls: nonexistent: No such file or directory
<-- blank

# Capture return code after command run in subshell (wrong)
$ (ls nonexistent 2>&1; rc=$?) | tee -a /dev/null; echo $rc
ls: nonexistent: No such file or directory
<-- blank

# Use I/O redirection with extra file descriptors (correct)
$ exec 3>&1; rc=`exec 4>&1; (ls nonexistent 2>&1; echo $? >&4) | tee -a /dev/null >&3`; exec 3>&-; echo $rc
ls: nonexistent: No such file or directory
1

# bash v2.0+ offers an easy-to-use PIPESTATUS array (correct)
$ ls nonexistent 2>&1 | tee -a /dev/null; echo ${PIPESTATUS[0]}
ls: nonexistent: No such file or directory
1

Regards,
Jared

Re: command | tee -a file

Suraj K Sankari — Wed, 20 May 2009 04:47:45 GMT

Hi,

If you dont want to show your output or first command then no need to give tee command.
tee command is showing the output of first command and send the same thing into the output file.

Suraj

Re: command | tee -a file

James R. Ferguson — Wed, 20 May 2009 11:19:26 GMT

Hi Den:

Another way (using a temporary file):

# (ls nofile 2>&1;echo $? > /tmp/rc.$$)|tee -a /dev/null;echo $(
Also, Den, please don't forget to evalulate the responses to some of your previous questions:

http://forums.itrc.hp.com/service/forums/questionanswer.do?threadId=1335784

Regards!

...JRF...

Re: command | tee -a file

Heironimus — Wed, 20 May 2009 18:30:45 GMT

If you want to avoid temp files and bash-specific variables....

rc=$({ { your-command ; echo $? 1>&3 ;} | tee -a output.txt 1>&2 ;} 3>&1) 2>&1
echo "rc=$rc"

Re: command | tee -a file

Leo The Cat — Mon, 25 May 2009 17:32:15 GMT

Thanks Guys