delay variable expansion


 
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# 1  
Old 03-02-2011
delay variable expansion

Hi forum,

in my bash script I've many lines executing commands with redirection to log files.
Code:
...
xyz_cmd   2>&1  > $BASENAME.$LINENO

The trailing part of these lines doesn't look nice and I like to put it into a variable.
The (not working) idea is something like that

Code:
REDIRECT='2>&1  > $BASENAME.$LINENO'
...
xyz_cmd  $REDIRECT

thanks for suggestions

Moderator's Comments:
Mod Comment Please use [code] and [/code] tags when posting code, data or logs etc. to preserve formatting and enhance readability, thanks.

Last edited by zaxxon; 03-02-2011 at 05:25 AM.. Reason: code tags
# 2  
Old 03-02-2011
You could try something like the following
Code:
#!/bin/bash

function logAction {
        COMMAND=$1
        LOGFILE=$2
        if [ "x$LOGFILE" == "x" ] ; then
                LOGFILE=myLog.log
        fi
        $COMMAND 2>&1 >> $LOGFILE
}

logAction ls fileList.log

Rather than substituting the redirect, write a logging function

Last edited by Skrynesaver; 03-02-2011 at 05:36 AM.. Reason: Was clobbering log file with each command issued
# 3  
Old 03-02-2011
Another way :
Code:
eval xyz_cmd  $REDIRECT

# 4  
Old 03-02-2011
Thanks to both of you.

In both solutions I've to pipe in the $LINENO at the calling point.
I want to avoid that.
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