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From: hamilton@uiucuxc.CSO.UIUC.EDU
Newsgroups: net.micro.amiga
Subject: Re: AmigaDOS problem
Message-ID: <148600129@uiucuxc>
Date: Wed, 20-Aug-86 20:17:00 EDT
Article-I.D.: uiucuxc.148600129
Posted: Wed Aug 20 20:17:00 1986
Date-Received: Sat, 23-Aug-86 02:11:49 EDT
References: <1646@well.UUCP>
Lines: 53
Nf-ID: #R:well.UUCP:1646:uiucuxc:148600129:000:2266
Nf-From: uiucuxc.CSO.UIUC.EDU!hamilton    Aug 20 19:17:00 1986


/* Written  8:53 pm  Aug 17, 1986 by crunch@well.UUCP in uiucuxc:net.micro.amiga */
/* ---------- "AmigaDOS problem" ---------- */
  I am trying to whip up a simple directory display program and want to
be able to detect when the last file has been displayed.   According
to the manual  which is INCORRECT and INACCURATE (Thank you, MetaCompco,
take a bow),  I quote from page 2-5 of the developers DOS (dog?) 
manual:

"ExNext gives a return code of zero if it fails for some reason.   One
 reason for failure is reaching the last entry of the directory.  However,
 IoErr() holds a code that may give more information on the exact cause of
 a failure.   WHEN ExNext FINISHES AFTER THE LAST ENTRY, IT RETURNS:
 ERROR_NO_MORE_ENTRIES (232)".   

FLAME ON:

 BULL BULL AND MORE BULL PILED HIGHER AND
 DEEPER!!

  Nothing can be further from the truth.   After EACH AND EVERY ExNext call
I get the ERROR_NO_MORE_ENTRIES returned values.

FLAME OFF:

  If anyone from Amiga cares to comment on this,  I would appreciate an
answer.   This is not only MY problem,  but a dozen other programmers from
the Programmers Net also would like the answers. 
/* End of text from uiucuxc:net.micro.amiga */

    john, the behavior you describe, suboptimal as it may be, does not
conflict with the documentation.  note that they did _NOT_ say:

	"[IoErr] returns [232] _ONLY_ after the last entry"

    it doesn't take that careful a reading to see that end-of-directory
is indicated by the conjunction (ExNext() == 0) _AND_ (IoErr() == 232).
the manual goes on to describe the procedure for walking a directory:

	"keep calling ExNext _until it fails_ with error code [==232]".

    i have written several programs that successfully walk the file system.
i just now modified one of them to print IoErr() after successful ExNext()s,
and i get a variety of values (232, 212, 205) even as correct results are
coming back (ie, the file info block stuff is right).  i'll post my code
if there's interest.

	wayne hamilton
	U of Il and US Army Corps of Engineers CERL
UUCP:	{ihnp4,pur-ee,convex}!uiucdcs!uiucuxc!hamilton
ARPA:	hamilton%uiucuxc@a.cs.uiuc.edu	USMail:	Box 476, Urbana, IL 61801
CSNET:	hamilton%uiucuxc@uiuc.csnet	Phone:	(217)333-8703
CIS:    [73047,544]			PLink: w hamilton