Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!husc6!mit-eddie!apollo!gaz
From: gaz@apollo.COM (Gary Zaidenweber)
Newsgroups: comp.sys.apollo
Subject: Re: name_$not_found status code
Message-ID: <431a2a92.ce45@apollo.COM>
Date: 8 May 89 17:25:00 GMT
References: <8905041340.AA03449@umix.cc.umich.edu>
Organization: Apollo Computer, Chelmsford, Mass.
Lines: 42

From article <8905041340.AA03449@umix.cc.umich.edu>, by FERGUSON@TMASL.EXXON.COM:
> 
> I tried to open a mailbox file that doesn't exist today, and received
> the status code = 0x800e0007
> When I do an error_$print on this status code, I get the error
> name not found from (OS/naming server). Therefore, I tried to
> put in a conditional like this:
> 
>       if (status.all == name_$not found) {
>             etc.
> 
> However, the name_$not_found status code in /sys/ins/name.ins.c
> is different by one bit. Instead of being 0x800e0007, it's
> 0x000e0007, and I don't know why. Obviously, I can kludge my
> way around this, but has anyone else noticed it?
> 
> I did an fpat (grep) on all of the /sys/ins/?*.c files as well as
> the .pas files, and the status code is not defined anywhere.
> Anyone know anything about this? Does the error handler ignore
> that first bit or something?
> 
> Thanks,
> Scott Ferguson
> ferguson@erevax.bitnet
> [
status_$t is a variant record (union). The top bit is a boolean
called "fail". See base.ins.pas for more info. I can't give you 
much information on how/why/who causes the "fail" bit to be set, 
but checking it like this:

	if ((status.all & 0x7FFFFFFF) == name_$not_found) {
		etc.

would be perfectly valid and would even yield the correct results :-)
Please note the bitwise AND (&) rather than a logical and (&&). Also
please forgive the pedantic explanation if you didn't need it.


-- 
Gary Zaidenweber        |   Its 1989:
UUCP:   umix!apollo!gaz |   Do you know where your lawyer is?
ARPA:   gaz@apollo.COM  |