Hello linux experts,

below code in a perl script throws error message when the particular job has not started yet. Is there a way to redirect the error output to somewhere else. Basically I dont want to see error/warning msgs in the output. I want the command to execute silently...

```
my @lines = `bjobs -l $job_id`;
```

Question

Hello linux experts,

below code in a perl script throws error message when the particular job has not started yet. Is there a way to redirect the error output to somewhere else. Basically I dont want to see error/warning msgs in the output. I want the command to execute silently...

```
my @lines = `bjobs -l $job_id`;
```

e.mccormick · Answer

There are ways to redirect stderr, but it has been a while so I don't know them off hand.  However, that is what you want to look into.  Redirecting stderr.

anonymous · Answer

Since you're calling some bash script/program (in between the two backticks), you can use the bash way of redirecting output. To get rid of any message that's printed on stderr, try `bjobs -l $job_id 2> /dev/null`. What it'll do is redirect stderr (stream 2) to /dev/null, which in this case is just a sink that discards the output.

Btw, how did you do the code formatting in your post?

ganeshie8 · Answer

i tried that it didnt work in my shell (tcsh). it is working only when I change my shell to ksh or bash. but my default shell is tcsh to which all other programs are tweaked. 

i have tried  bjobs -l $job_id >& /dev/null, but it is redirecting stdout also, actually i wanto capture output if theres any, and i want it redirect only stderr...

ganeshie8 · Answer

there doesnt seem to be a way in tcsh to do this :(

e.mccormick · Answer

Ah!  tsch.  Did you look at the man page?

"The shell cannot presently redirect diagnostic output without also redirecting standard output, but `(command > output-file) >& error-file' is often an acceptable  workaround. Either output-file or
error-file may be `/dev/tty' to send output to the terminal."