[comp.sys.mac.hypercard] Writing an XCMD with THINK C 4.0

unruh@cadlab2.ecn.purdue.edu (Vance W Unruh) (06/08/91)

I am trying to write an XCMD with THINK C 4.0 and have run into some problems.

First, while reading the 'HyperCard Script Language Guide' which came with
my Claris upgrade to version 2.0v2, I discovered that the list of 'request
codes' for "Callback procedures and functions" is not in the manual. (at 
least not where I could find it :)  The last sentence on page 450 states that
the codes are listed in the next section.  I have looked through that section
several times and connot find them.  How can I use the callback functions
without these codes?

Second, I would appreciate any tips on using the 'SetUpA4' utilities in 
THINK C which allow the use of global variables in XCMD's.  I have a rough
understanding of them, but was wondering when they should be called in relation
to the callback functions and in relation to procedures called from the ToolBox
such as the procedure which can be called from TrackControl.

Thanks for any help

Vance Unruh
unruh@ecn.purdue.edu