[plt-scheme] High precision timing and MrEd/OSX

From: Rohan Drape (rd at alphalink.com.au)
Date: Mon Dec 20 19:30:47 EST 2004

A recent message on this subject got no response so I will 
try again and hopefully be clearer.

I would like to do accurate scheduling in PLT on OSX.

I could not find anything in the distribution so I wrote 
an extension based on setitimer.

This extension works well enough under mzscheme/Linux and
MrEd/Linux, and under mzscheme/OSX, but fails under MrEd/OSX.

I think this may be a problem with MrEd/OSX using SIGALRM internally.

My questions are:

1. Is the a high precision timer that already works somewhere?
2. Is there something I can do to MrEd to get this extension 
   to work as it is?
3. If I need to rewrite the extension:
     a. Is there an OSX timer that is known to work with MrEd.
     b. Is the basic design flawed (ie. should I do this 

My inital post, with more detail, is at:


Any help would be much appreciated.


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