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04cc463452
Please refer to https://github.com/cc65/cc65/pull/532 for background info.
I wrote in https://sourceforge.net/p/cc65/mailman/message/35873183/
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cputs() wraps to the next line if the strings is too long to fit in the current line. I don't know if it's worth the effort to allow cpeeks() to continue reading from the next line. I'd like to discuss this aspect with the actual implementers.
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This is still as unclear today as it was when I wrote the above. Therefore this change just doesn't add cpeeks() at all.
Since f8c6c58373 the Apple II CONIO implementation doesn't "need" revers() anymore - meaning that (nearly) every possible value can be placed in VRAM with a straight cputc() (without the need for a previous revers(1)).
The implementation of cpeekc() leverages that cputc() ability by always returning the value that can be fed into cputc() without a previous revers(1). Accordingly, cpeekrevers() always returns 0.
So after the sequence revers(1); cputc(x); a cpeekc() will return a value different from x! However, I don't see this behavior braking the cpeekc() contract. I see the cpeekc() contract being defined by the sequence textcolor(cpeekcolor()); revers(cpeekrevers()); cputc(cpeekc()); placing the very same value in VRAM that there was before. And that contract is fulfilled.
cc65 is a complete cross development package for 65(C)02 systems, including a powerful macro assembler, a C compiler, linker, librarian and several other tools.
cc65 has C and runtime library support for many of the old 6502 machines, including
- the following Commodore machines:
- VIC20
- C16/C116 and Plus/4
- C64
- C128
- CBM 510 (aka P500)
- the 600/700 family
- newer PET machines (not 2001).
- the Apple ][+ and successors.
- the Atari 8-bit machines.
- the Atari 2600 console.
- the Atari 5200 console.
- GEOS for the C64, C128 and Apple //e.
- the Bit Corporation Gamate console.
- the NEC PC-Engine (aka TurboGrafx-16) console.
- the Nintendo Entertainment System (NES) console.
- the Watara Supervision console.
- the VTech Creativision console.
- the Oric Atmos.
- the Oric Telestrat.
- the Lynx console.
- the Ohio Scientific Challenger 1P.
The libraries are fairly portable, so creating a version for other 6502s shouldn't be too much work.