Inconsistency between MAKEDEV and lp.c
Steve Campbell
steve at dartvax.UUCP
Sat Jun 9 03:31:29 AEST 1984
Index: sys/vaxuba/lp.c /dev/MAKEDEV 4.2BSD
Description:
MAKEDEV assigns sequential minor device numbers - 0,1,2,... - to
lp devices lp0, lp1, lp2, etc. The driver, however, determines
the unit address by shifting the minor device number >> 3, using
the 3 low-order bits for software flags. Hence the driver
wants minor device numbers 0,8,16,etc.
Repeat-By:
Configure two line printers, lp0 and lp1. MAKEDEV will give
them minor device numbers 0 and 1. Lp0 will work ok, but
if you use lp1, the driver still sends the data to lp0. What's
more, the data will be mapped to upper case, since the "1"
bit is treated as a "map-to-upper" flag by the driver.
Fix:
Take your pick: either hack MAKEDEV to generate the right minor
device numbers for lp's, or fix the driver to use regular,
sequential, minor device numbers and do the flags another way.
---------------------------------------------------------------------
Steve Campbell
UUCP: {decvax|linus|cornell|astrovax}!dartvax!steve
CSNET: steve at dartmouth ARPA: steve%dartmouth at csnet-relay
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