How to Force command substitution evaluation in bash? Post: 302969879

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Top Forums Shell Programming and Scripting How to Force command substitution evaluation in bash? Post 302969879 by siegfried on Tuesday 29th of March 2016 01:56:05 PM

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03-29-2016

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Yes! As I you inferred: $(BackupRecords --log) very similar to $(date +'%Y %b %d %H:%M:%ss'). If I call it too often, I get different log files (which is usually what I want).

However, in this case, I want the same log file for multiple uses within the same script. How can I evaluate $(BackupRecords --log) only once at the beginning of my script once and use it multiple times later in the script?

Thanks
Siegfried

siegfried

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LEARN ABOUT SUSE

bf_tar

BF_TAR(1)																 BF_TAR(1)

NAME

       bf_tar - shell script to write a tar file of a bogofilter directory to stdout

SYNOPSIS

       bf_tar [-r] [-R] bogofilter_directory

DESCRIPTION

       bf_tar bundles a bogofilter working directory in tar format and copies it to standard output (your console, or where you redirect it, see
       EXAMPLES below).

OPTIONS

       The -r option causes bf_tar to remove inactive log files after the archive has been written successfully. The default is to leave log
       files.

       The -R option causes bf_tar to remove inactive log files before the archive is written. This may reduce chances that the resulting archive
       is recoverable should it become damaged. The archive may be smaller though. The default is to leave log files.

EXIT STATUS

       The script exits with status code 0 if everything went well, and nonzero if it encountered trouble.

EXAMPLES

       o  bf_tar ~/.bogofilter > outfile.tar

	  Writes a standard .tar file containing the essential files from ~/.bogofilter to outfile.tar.

       o  bf_tar ~/.bogofilter | gzip -9 -c > outfile.tar.gz

	  Writes a gzipped .tar.gz file containing the essential files from ~/.bogofilter to outfile.tar.gz.

       o  bf_tar `pwd`/mydirectory > outfile.tar

	  Prepend $(pwd)/ or `pwd`/ if you want to specify an absolute path instead of a relative path.

NOTES

       This script is meant for use with Berkeley DB based bogofilter versions.

       This script requires a SUSv2 compliant pax utility.

       This script expects a SUSv2 compliant shell. Solaris systems should have the SUNWxcu4 package installed (when bogofilter is configured) so
       that /usr/xpg4/bin/sh can be used.

								    07/23/2007								 BF_TAR(1)