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Full Discussion: Semaphore
Top Forums Shell Programming and Scripting Semaphore Post 302304056 by rouilj on Saturday 4th of April 2009 05:10:44 PM
Old 04-04-2009
MySQL

I managed to grab a semaphore implementation in ksh originally written by
Ed Schaefer and John Spurgeon for UNIX Review in 2004. The original has dissappeared but my slightly fixed copy is available at:

http://www.cs.umb.edu/~rouilj/#Semaphore

In addition to per user seamphores it also supports a queing mechanism to help prevent starvation.

The only current issue with it is that it works only on a single machine,
I have a plan on how to make it work across multiple machines, but that's not implemented yet.

-- rouilj
 

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SVNPATH(1)																SVNPATH(1)

NAME
svnpath - output svn url with support for tags and branches SYNOPSIS
svnpath svnpath tags svnpath branches svnpath trunk DESCRIPTION
svnpath is intended to be run in a Subversion working copy. In its simplest usage, svnpath with no parameters outputs the svn url for the repository associated with the working copy. If a parameter is given, svnpath attempts to instead output the url that would be used for the tags, branches, or trunk. This will only work if it's run in the top-level directory that is subject to tagging or branching. For example, if you want to tag what's checked into Subversion as version 1.0, you could use a command like this: svn cp $(svnpath) $(svnpath tags)/1.0 That's much easier than using svn info to look up the repository url and manually modifying it to derive the url to use for the tag, and typing in something like this: svn cp svn+ssh://my.server.example/svn/project/trunk svn+ssh://my.server.example/svn/project/tags/1.0 svnpath uses a simple heuristic to convert between the trunk, tags, and branches paths. It replaces the first occurrence of trunk, tags, or branches with the name of what you're looking for. This will work ok for most typical Subversion repository layouts. If you have an atypical layout and it does not work, you can add a ~/.svnpath file. This file is perl code, which can modify the path in $url. For example, the author uses this file: #!/usr/bin/perl # svnpath personal override file # For d-i I sometimes work from a full d-i tree branch. Remove that from # the path to get regular tags or branches directories. $url=~s!d-i/(rc|beta)[0-9]+/!!; $url=~s!d-i/sarge/!!; 1 LICENSE
GPL version 2 or later AUTHOR
Joey Hess <joey@kitenet.net> Debian Utilities 2013-12-23 SVNPATH(1)
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