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Full Discussion: Please can any one explain this ${0##/}
Top Forums Shell Programming and Scripting Please can any one explain this ${0##/} Post 302180965 by unilover on Tuesday 1st of April 2008 03:26:42 PM
Old 04-01-2008
PGM=${0##/}
TMP=/tmp/${PGM}.$$

$0 is the complete-name-of-the-script in side the script (e.g. /home/mydir/myscript.sh)

So, ${0##/} means the complete-name-of-the-script without the starting-slash (if it exists)!!

But, what I thing you wanted to write is:

PGM=${0##*/}

which means complete-name-of-the-script without everthing up to and including the last-slash (e.g. myscript.sh)

Then, $$ is the Process-ID of the current script. So, TMP will be set to be /tmp/myscript.sh.1234 (where 1234 is the process-id).

This combination is normally used to create unique (i.e. different for each running script) names.
 

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LEARN ABOUT DEBIAN

build-lives-rfx-plugin

build-lives-rfx-plugin(1)				      General Commands Manual					 build-lives-rfx-plugin(1)

NAME

       build-lives-rfx-plugin - builds rendered effects for LiVES

SYNOPSIS

       build-lives-rfx-plugin script_name [plugin_dir] -get section file

DESCRIPTION

       This perl script is used by LiVES to compile an RFX (rendered effect) plugin for LiVES. It is generally called from build-lives-rfx-plugin-
       multi for a script which has a language code representing LiVES-perl. The script_name must be  the  full  (absolute)  path  to  the  plugin
       script,	and  plugin_dir  can  be  used to specify the output directory where the compiled plugin should be generated. If plugin_dir is not
       defined then /tmp is assumed.

       The second variant with -get is used to print out a script section from a plugin script to stdout. It is generally only used internally	by
       LiVES.

       Return values The script returns the following values

       0 - success 1 - the value of a trigger was greater than the number of parameters 2 - a value could not be read from the script file 3 - the
       language code of the plugin script was not equivalent to LiVES-perl 4 - the API version level of the plugin script  was	invalid  5  -  the
       <define> section was missing from the plugin script

SEE ALSO

       build-lives-rfx-plugin-multi(1), lives(1)

AUTHOR

       Gabriel Finch a.k.a Salsaman (salsaman@xs4all.nl)

								    May 9 2010						 build-lives-rfx-plugin(1)
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