Rocksolid Light - comp.os.cpm - Random Read bug fix for DRI CPM3

Random Read bug fix for DRI CPM3

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https://news.novabbs.org/devel/article-flat.php?id=5115&group=comp.os.cpm#5115

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From: dxforth@gmail.com (dxf)
Newsgroups: comp.os.cpm
Subject: Random Read bug fix for DRI CPM3
Date: Sun, 17 Sep 2023 23:06:20 +1000
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by: dxf - Sun, 17 Sep 2023 13:06 UTC

; ZPM3's Random Read bug fix applied to DRI BDOS30.ASM
; Source: http://cpmarchives.classiccmp.org/cpm/mirrors/www.triton.vg/tesseract/pds/093/zpm3s.arc
; NOTE: ONLY BRIEFLY TESTED

; Extent is in same directory fcb
push b! call get$dir$ext! pop b
cmp c
jz rrfix ;*** in last extent: treat as new area!
jnc rseek2 ; jmp if dir$ext > ext
pop d! push d! inr e! jnz rseek2 ; jmp if write fx
inr e! pop d! jmp set$lret1 ; error - reading unwritten data
rrfix:
pop d! push d ;*** get&save read flag (in E)
inr e! jnz rseek2 ;*** are we reading? no: ok, open this extent
lhld info! xchg! jmp ranclose ;*** yes: close extent and open
rseek2:

Additions are marked ***.

To verify the random read bug is quashed see rrbug.zip
https://drive.google.com/drive/folders/1kh2WcPUc3hQpLcz7TQ-YQiowrozvxfGw

The less time planning, the more time programming.

devel / comp.os.cpm / Random Read bug fix for DRI CPM3

Subject	Author
Random Read bug fix for DRI CPM3	dxf