FATQW@USU.BITNET (02/20/88)
Why is APTR defined to be a pointer to a pointer (STRPTR) to UBYTEs???
Bryan
Bryan Ford //// A computer does what \\\\
Snail: 1790 East 1400 North //// you tell it to do, not \\\\
Logan, UT 84321 \\\XX/// what you want it to do. \\\XX///
Email: FATQW@USU.BITNET \XXXX/ Murphy's Law Calendar 1986 \XXXX/rap@ardent.UUCP (Rob Peck) (02/23/88)
In article <8802200055.AA00454@jade.berkeley.edu>, FATQW@USU.BITNET writes: > Why is APTR defined to be a pointer to a pointer (STRPTR) to UBYTEs??? As I remember, Carl Sassenrath wanted to have something that was a generic pointer variable and this is what he came up with. The side effect of this choice was that if: APTR p; then when you later used p++; it would only increment the pointer by the size of one long word. (if p == 0x10000, then p++ == 0x10004). Not sure exactly what the "full" reason, but this is part of it. (It may also have some bearing on one of the macros that converts an APTR to a BPTR and vice versa. If APTR was badly defined, the C compiler could have a field day with the value it returns.) Rob Peck (Amiga-history-buff) ...ihnp4!hplabs!ardent!rap
cks@radio.toronto.edu (Chris Siebenmann) (02/24/88)
In article <8802200055.AA00454@jade.berkeley.edu> FATQW@USU.BITNET writes: >Why is APTR defined to be a pointer to a pointer (STRPTR) to UBYTEs??? I've always assumed that this was a mistake that stayed around for backwards compatability. Does anyone know for sure? -- "I shall clasp my hands together and bow to the corners of the world." Number Ten Ox, "Bridge of Birds" Chris Siebenmann {allegra,mnetor,decvax,pyramid}!utgpu!radio!cks cks@radio.toronto.edu or ...!utgpu!{chp!hak!ziebmef,ontmoh}!cks
dillon@CORY.BERKELEY.EDU (Matt Dillon) (02/25/88)
An APTR is an APTR is an APTR. It means what it means. The only "mistake" about it is that some people assume it is something other than what it is. -Matt Matt Dillon Dillon