Re: A89: gettin' started


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Re: A89: gettin' started




I realize this, this is how SOS for the 83 does libraries, but it uses
pointers. Which mean you call a location that calls the library, but if
you ever have stepped through a program in VTI you see that it is a jsr
right to the location of the library routine

Kaus wrote:
> 
> Actually, I am pretty sure that what is really done is that each library
> reference is replaced with a call to the OS with the function number as an
> argument of some sort. then, the OS finds the library (if available) looks
> in its function offset table, and jumps to the correct function in the
> library code.  This is proven by the fact that you never have to code
> anything that says: "This program needs library so and so to run" and abort.
> This is done in the OS's library calling code if the library can't be found.
> 
> --kaus
> 
> ----- Original Message -----
> From: Scott Dial <wrath@calc.org>
> To: <assembly-89@lists.ticalc.org>
> Sent: Wednesday, December 29, 1999 10:06 PM
> Subject: Re: A89: gettin' started
> 
> >
> > I have a question about this too, the way I have seen this done is using
> > a static location to jump to that jumps to the dynamic one. But, it
> > obviously comes up with the address during linking or whatever which
> > makes no sense to me because it can never be in the same spot. So how is
> > this done?
> >
> > Cassady Roop wrote:
> > >
> > > so does the library have to be on the calculator for the program to
> > > run?  If so, then how is it so simple to reference a library call if the
> > > library is a variable separate from the program?
> > >
> > > Cassady Roop
> > >
> > > KeysDezes@aol.com wrote:
> > > >
> > > > <A
> HREF="http://calccity.calc.org/tiweekly/Articles/Beginners_TI89_ASM.html">B
> > > > eginners Guide to TI-89/92+ Assembly</A>
> > > > By far, the most comprehensive guide to 68k asm that I've seen.
> > > > Libraries are sets of routines that can be accessed by asm programs.
> The
> > > > advantage of libraries is that they are shared by all programs.  They
> contain
> > > > common routines such as PutSprite and clr_scr.
> >
> > --
> > Scott "_Wrath_" Dial
> > wrath@calc.org
> > ICQ#3608935
> > TimeCity AI Guy II - www.timecity.org
> > Member of TCPA - tcpa.calc.org
> > __________________________________________
> > NetZero - Defenders of the Free World
> > Get your FREE Internet Access and Email at
> > http://www.netzero.net/download/index.html
> >

-- 
Scott "_Wrath_" Dial
wrath@calc.org
ICQ#3608935
TimeCity AI Guy II - www.timecity.org
Member of TCPA - tcpa.calc.org
__________________________________________
NetZero - Defenders of the Free World
Get your FREE Internet Access and Email at
http://www.netzero.net/download/index.html


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