[comp.sys.mac.programmer] MPW Tools Globals ?

ews00461@uxa.cso.uiuc.edu (08/01/90)

How do MPW tools handle global data ?  I'm trying to develop my
own format for  dynamically linked code, something along the lines
of MPW tools.  I want to be able to execute the code inside a file,
like tools, and have global data.  Is A5 patched on entry to the
tool ?  Do tools have their own jump table separate from MPW Shell ?
Don't tools access some of MPW's A5 globals?  How do tools call
MPW stdio ?  What code is contained in these stdio libraries ?

While we're close to the topic, how do some MPW compilers handle >32k
of global data ?  The 68000 cannot access this using 16 bit
displacement from a5.

Any discussion on this/these topics would be interesting to me,
including explanations of XCMD's, Excel DLL's, XFCN, etc...

Eric W. Sink
e-sink@uiuc.edu