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Full Discussion: [Solved] BASH - chaining TEST and COMMAND with && and II
Top Forums Shell Programming and Scripting [Solved] BASH - chaining TEST and COMMAND with && and II Post 302725359 by jcdole on Friday 2nd of November 2012 06:28:46 AM
Old 11-02-2012
[Solved] BASH - chaining TEST and COMMAND with && and II
Can you explain what this line of script is doing.
What I have understood is :
-- variable C is the name of a software which is either not installed, so it must be installed or allready installed and then should be update if newer version found
-- branch B="$B $C" is to install the software
-- branch D="$D $C" is to update the software

How does [ "$A" == "0" ] && B="$B $C" || D="$D $C" works ?
Code:
A="0" or not
B=""
C="a_software-5.4.3-7.x86_64.rpm"
D=""
#
Download_the_package_and_put_it_in_tmp_directory   $C
#
if [ -f /tmp/$C ] ; then
    [ "$A" == "0" ] && B="$B $C" || D="$D $C"
else
        echo "Package not found"
fi

Help would be appreciated.
 

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LEARN ABOUT DEBIAN

gbp-pull

GBP-PULL(1)						      git-buildpackage Manual						       GBP-PULL(1)

NAME

       gbp-pull - Safely update a repository from remote

SYNOPSIS

       gbp-pull  [ --verbose ] [ --force ] [ --redo-pq ] [ --[no-]pristine-tar ] [ --debian-branch=branch_name ] [ --upstream-branch=branch_name ]
       [ --depth=depth ]

DESCRIPTION

       gbp-pull updates the debian, upstream and pristine-tar branches from a remote repository in one go. It checks if the update is safe  (would
       result in a fast-forward merge) and aborts otherwise.

OPTIONS

       --force
	      force a branch update even if this results in a non fast forward update.

	      Warning: Forcing a branch updates makes you lose your modifications.

       --redo-pq
	      also rebuild the corresponding patch-queue using gbp-pq.

	      Warning: This drops the patch-queue branch if it exists.

       --debian-branch=branch_name
	      The branch in the Git repository the Debian package is being developed on, default is master.

       --upstream-branch=branch_name
	      The branch in the Git repository the upstream sources are put onto. Default is upstream.

       --depth=depth
	      Git history depth, for deepening shallow git clones.

       --verbose

       -v     verbose execution

       --pristine-tar
	      Whether to update the pristine-tar branch too.

EXIT CODES

       When gbp-pull finishes it indicates success or failure with it's exit code:

       0      Success.

       1      An error occured during the pull, see the printed error message for details.

       2      At least one branch couldn't be fast forwarded.

CONFIGURATION FILES

       Several	gbp.conf  files  are  parsed  to  set defaults for the above commandline arguments. See the [XRef to GBP.MAN.GBP.CONF] manpage for
       details.

SEE ALSO

       git-buildpackage(1), gbp-clone(1), gbp-pq(1), gbp.conf(5)

AUTHOR

       Guido Guenther <agx@sigxcpu.org>

								   01 June 2012 						       GBP-PULL(1)
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