Shell Script - Output background process command to file problem

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August 3rd, 2004, 01:57 PM

pinemind

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Shell Script - Output background process command to file problem

Hi everyone,

Just started shell scripting for some simple tasks in Solaris 8. Here's my problem. I'm running a shell script from the crontab file to start and stop some services. There is a list of commands like the following

Code:

#!/bin/csh

$DIR/runthis stop >> logfile
date >> logfile

$DIR/runthis2 stop >>logfile
date >> logfile

$DIR/runthis start & 
date >> logfile

$DIR/runthis2 start &
date >> logfile

Outputting the stop commands and date info to the logfile works fine. The problem is, I need to output the stdout of the commands issued in the background (&). If I put the append command (>>) after the ampersand (space or no space) with the logfile name, I get an "Invalid null char" error.

I have searched the web to try and find out how you can append the output of a background process command to a file and there is nothing about it. I know the command outputs to the console because if I run it by itself, I get the output desired.

Is there anyway to capture the output of a background process?

Peace,

Justin

August 3rd, 2004, 06:41 PM

Perderabo

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Posts: 121

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I don't use csh very much, but try:
runthis start >> logfile &

August 3rd, 2004, 11:11 PM

guggach

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Justin

csh on command line is an exceleent tool.
csh in scripts is buggy, don't use it at all.
what you want is:

Code:

#!/bin/sh
   (
   do-this
   do-that
   do-more &
   ) >logfile

or '>>logfile' for append
remember cron has a very restricted environment, so
$DIR maybe NOT set.

August 4th, 2004, 08:38 AM

pinemind

Registered User

Join Date: Jul 2004

Posts: 15

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guggach,

By aggregating the commands together, will the logfile still contain the output from each separate command or just the last one in the list?

Justin

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