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From: kurash@chocorua.dartmouth.edu (Mark Valence)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Probably a simplistic question, but I haven't seen the answer
Summary: A less simple answer
Keywords: GetVol, PMSP
Message-ID: <24323@dartvax.Dartmouth.EDU>
Date: 17 Sep 90 16:46:51 GMT
References: <DKF%9*%@rpi.edu> <701@sun13.scri.fsu.edu>
Sender: news@dartvax.Dartmouth.EDU
Reply-To: kurash@chocorua (Mark Valence)
Distribution: comp
Organization: Dartmouth College
Lines: 45

In article <701@sun13.scri.fsu.edu> pepke@gw.scri.fsu.edu (Eric Pepke) writes:
>The answer, at least, is simple.  Don't use HFS calls.  Use MFS calls.
>The folder in which the application sits is in the Poor Man's Search Path.

That's certainly one simple answer.  In case the original poster does
not know what the Poor Man's Search Path is (if you only have IM I & II,
you may not know), it is the 'list' of folders the File Manager checks
whenever you Open files (or do various other operations).

Another way to do this is to make this call immediately after your
manager Initialization (_InitGraf,...,_InitWindows, TEInit, etc):

theErr := GetVol(nil, appFolder);

(in this case theErr:OSErr and appFolder:integer)

This way you can have the VRefNum of the folder from which
your application was launched at the tip of your fingers
for the entire time your program runs.

When you do an FSOpen call:

theErr := FSOpen(fileName, appFolder, refNum);

alternately, for a PBOpen:

...
pb.ioVRefNum := appFolder;
...
theErr := PBOpen(@pb, false);

These calls are similar in C, if that's your preference.

>Eric Pepke                                    INTERNET: pepke@gw.scri.fsu.edu
>Supercomputer Computations Research Institute MFENET:   pepke@fsu
>Florida State University                      SPAN:     scri::pepke
>Tallahassee, FL 32306-4052                    BITNET:   pepke@fsu
>
>Disclaimer: My employers seldom even LISTEN to my opinions.
>Meta-disclaimer: Any society that needs disclaimers has too many lawyers.

Any society that *has* lawyers has too many lawyers.  Attorneys are
another story.

Mark.