[comp.windows.x] Are _Xxxxx routines supposed to be visible?

taylort@decus.com.au (Trevor Taylor) (02/26/91)

I'm currently porting the MIT R4 clients to VMS and I have found
that xpr and xwud call a routine _XInitImageFuncPtrs() so that
they can manipulate an image structure using the Xlib routines
without actually creating an image. 

The problem is that VMS uses shared libraries, and very few of
the _Xxxxx routines are visible. Now to the question:
Are these "internal" routines supposed to be available to the
applications programmer?

Would anyone in the Consortium care to answer? If they are
part of the definition (which I doubt) then should DEC be
making them accessible?

Failing that, should this routine have an external interface
in R5? It's not very polite for the MIT code to "cheat" :-)

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rws@expo.lcs.mit.EDU (Bob Scheifler) (02/27/91)

    Are these "internal" routines supposed to be available to the
    applications programmer?

The Xlib XImage functional design is quite broken, and no one has had
the stomach to fix it.  The problem here is that XCreateImage obtains
several parameters from the display argument, there is no way to
specify explicit values when the data is coming from a file.  This
is ludicrous.  Since the internal functions stored in the XImage
can depend on these values, xwud is calling an internal function
to get the job done.  Perhaps, someday, this will all get fixed.