Odd code in boot/sys.c

Odd code in boot/sys.c

Post by Paul Newhou » Thu, 30 May 1996 04:00:00



I found the following code in boot/sys.c (-current).  Which goes a long way in explaining
why I can't boot from my third IDE disk (Secondary Master):

                if (*cp >= '0' && *cp <= '9')
                        if ((unit = *cp++ - '0') > 1) {
                                printf("Bad unit\n");
                                return 1;
                        }

I'm at a loss as to why the code checks for the character pointed at by cp to
be within the range 0-9, inclusive, and then after decoding it decides to limit
the range to 0 or 1??  

You don't get "Bad unit", if you specify 'x' instead of 0-9.

Is there a problem with using 2 or 3 in the boot line:  "wd(2,a)/netbsd"
I was pretty sure I had this working on a previous version of NetBSD (maybe it was
FreeBSD or BSDI???).

I thought I'd ask before changing the "> 1" to "> 9".  Just incase there is some
really bad thing that can happen.  Suggestions, comments, actual knowledge
are appreciated.

Thanks,
Paul
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