Jonathan de Boyne Pollard wrote in a message to Jason Weill:

 JdBP>   There *is* a REXX solution to this, and it's about the
 JdBP> best solution   that you can achieve.

 JdBP>   The solution is to use *real* semaphores, not flag files.

 JdBP>   OS/2 provides real semaphores, and there is at least one
 JdBP> REXX extension   package (called RXU) available on FIDONET
 JdBP> files sites that allows you to   control semaphores from
 JdBP> REXX scripts.  You can thus write your REXX   scripts to use
 JdBP> event semaphores.

Or someone could get this by FReq (1:323/107) or download (+1 401 944 8498):

MUTEX021.ZIP   13K  3-05-95  OS/2 Mutual Exclusion Manager 950226v0.21(beta)

This simply waits for a named semphore and then spawns whatever program or
batch file is supplied on the command line.  REXX is a good solution for
programmers or people who want to learn REXX, but Mutex is a quick and
dirty solution for people who do not.
 
-- Mike


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