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in article <13291@gryphon.COM>, ddave@pnet02.cts.com (David Donley) says:

> HELP!  I am trying to write a mountlist writing program.  Could somebody
> please tell me

> 1. How can you tell if a BSTR or BPTR is NULL?

Well, start with the BPTR.  Based on the definition:

	BPTR = CPTR >> 2;

One would expect a BPTR NULL to be 0>>2, which magically turns out to be
the same as the CPTR NULL.  Imagine that.

A BCPL string (once de-referenced, of course) is empty is the first byte
is 0.  You may also note that again, in this one case, that's the same
way you tell if a C string is empty.  Of course, before de-referencing a
BCPL string pointer, you'll have to check that it's non-NULL, and probably 
shift it's pointer into a CPTR, as most BCPL strings are pointed to by
BPTRs.

> 2. What has changed in the FileSysStartupMsg, DeviceNode, and fssm_Environ
> since 1.2?

The only thing I know of is that the environment is longer.  The first longword
of the environment tells you it's length.  Under 1.2, DE_MEMBUFTYPE is the
last word of the environment.  Under 1.3, you can also have the following
environment vector members (in order):

	ULONG DE_MAXTRANSFER	The maximum number of bytes to transfer
				at a time.
	ULONG DE_MASK		Address mask used to block out certain
				areas of memory.
	 LONG DE_BOOTPRI	Autoboot priority.
	ULONG DE_DOSTYPE	Indicates the file system, SFS = 'DOS\0',
				FFS = 'DOS\1'

>         ddave@pnet02.CTS.COM ddave@pnet.gryphon.COM killer!gryphon!pnet02!ddave
-- 
Dave Haynie  "The 32 Bit Guy"     Commodore-Amiga  "The Crew That Never Rests"
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