Set up GUI stack on OSX server that handles STDIN/STDOUT

[Sannyasin Sivakatirswami]

General Question is:

How does one set up a stack on an OSX server that can act like a UNIX 
program where any other [Program A] can set a path:

  /usr/sbin/myFilter.mc

where myFilter.mc is an open stack running in GUI mode,
such that output from Program A is read as standardIn incoming data by 
'myFilter.mc" to which
myFilter.mc can send our responses which are seen by Program A
as data coming from myFilter.mc's standardOut?

Specific Context is:

We want to have more control over incoming email on the email server, 
not only for virus scanning but for many other purposes. Communigate 
Pro (our mail server) can set up a path to an external program and 
using its "External Filter API"  which is a simple set or 
request/response codes, it will send a request to the external program 
and expect responses. I would like the external program to be a 
metacard stack if possible, with a GUI interface.

Is that doable? In this scenario Apache or any web CGI interfaces are 
not involved. But i think it must be a similar concept as Pierre 
Sohores "long running process"

i know how to use the faceless script to "read from stnin"

but how do you do that in a GUI stack ... which must be some how set up 
a pipe to "listen" ?

mmm. somehow.  I think we may have come full circle here back to 
Metacard's roots?

examples stack and scripts would be very helpful...

Sannyasin Sivakatirswami
Himalayan Academy Publications
at Kauai's Hindu Monastery
katir at hindu.org

www.HimalayanAcademy.com,
www.HinduismToday.com
www.Gurudeva.org
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