How to Force command substitution evaluation in bash? Post: 302969894

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Top Forums Shell Programming and Scripting How to Force command substitution evaluation in bash? Post 302969894 by Don Cragun on Tuesday 29th of March 2016 04:16:54 PM

Old

03-29-2016

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Quote:

Originally Posted by shamrock

Set BUPLOG to be readonly by doing typeset -x -r BUPLOG=$(BackupRecords --log "$src")so the script will throw an error every time it's changed...

We have seen the script. There is nothing in it that changes BUPLOG after it is initially set. As I have said before, BUPLOG must be a string something like:

Code:

BackupLog$(date +'%Y%m%d%H%M%S')

so when $BUPLOG is expanded it yields a value based on the current time; not the time when BackupRecords --log was executed at the start of the script.

Don Cragun

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backuplog

BACKUPLOG(5)							AFS File Reference						      BACKUPLOG(5)

NAME
       BackupLog - Traces Backup Server operations

DESCRIPTION
       The BackupLog file records a trace of Backup Server (buserver process) operations on the local machine and describes any error conditions
       it encounters.

       If the BackupLog file does not already exist in the /var/log/openafs directory when the Backup Server starts, the server process creates it
       and writes initial start-up messages to it. If there is an existing file, the Backup Server renames it to BackupLog.old, overwriting the
       existing BackupLog.old file if it exists.

       The file is in ASCII format. Administrators listed in the /etc/openafs/server/UserList file can use the bos getlog command to display its
       contents. Alternatively, log on to the machine and use a text editor or a file display command such as the UNIX cat command. By default,
       the mode bits on the BackupLog file grant the required "r" (read) permission to all users.

       The Backup Server records operations only as it completes them, and so cannot recover from failures by reviewing the file. The log contents
       are useful for administrative evaluation of process failures and other problems.

SEE ALSO
       UserList(5), bos_getlog(8), buserver(8)

COPYRIGHT
       IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.

       This documentation is covered by the IBM Public License Version 1.0.  It was converted from HTML to POD by software written by Chas
       Williams and Russ Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.

OpenAFS 							    2012-03-26							      BACKUPLOG(5)