Path: utzoo!mnetor!uunet!mcvax!guido
From: guido@cwi.nl (Guido van Rossum)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Full path name of a file
Message-ID: <301@piring.cwi.nl>
Date: 6 May 88 10:44:41 GMT
References: <2532@chalmers.UUCP>
Reply-To: guido@cwi.nl (Guido van Rossum)
Organization: The Royal Society for Prevention of Cruelty to Amoebae
Lines: 76

In article <2532@chalmers.UUCP> olausson@chalmers.UUCP (Stefan Olausson) writes:
>Given the information in a SFReply, how do I construct the full path name
>of a file (as a string), i e "disk:dir1:dir2:...:filename" ?

Here's my code.  I am not posting the header file "macdefs.h" or the
"dprintf" routine but you should be able to gues what's in them.; or ask
me to mail them.  This was tested with MPW.

/* GET FULL PATHNAME OF A FILE.
   Public Domain by Guido van Rossum, CWI, Amsterdam. May 1988. */

#include "macwin.h"

/* Mac file system parameters */
#define MAXPATH 256	/* Max path name length+1 */
#define SEP ':'		/* Separator in path names */
#define ROOTID 2	/* DirID of a volume's root directory */

/* Macro to find out whether we can do HFS-only calls: */
#define FSFCBLen (* (short *) 0x3f6)
#define hfsrunning() (FSFCBLen > 0)

char *
getdirname(dir)
	long dir; /* WDRefNum */
{
	union {
		HFileInfo f;
		DirInfo d;
		WDPBRec w;
		VolumeParam v;
	} pb;
	static char cwd[2*MAXPATH];
	char namebuf[MAXPATH];
	short err;
	long dirid= 0;
	char *next= cwd + sizeof cwd - 1;
	int len;
	
	if (!hfsrunning())
		return "";
	
	for (;;) {
		pb.d.ioNamePtr= namebuf;
		pb.d.ioVRefNum= dir;
		pb.d.ioFDirIndex= -1;
		pb.d.ioDrDirID= dirid;
		err= PBGetCatInfo(&pb.d, FALSE);
		if (err != noErr) {
			dprintf("PBCatInfo err %d", err);
			return NULL;
		}
		*--next= SEP;
		len= namebuf[0];
		/* There is no overflow check on cwd here! */
		strncpy(next -= len, namebuf+1, len);
		if (pb.d.ioDrDirID == ROOTID)
			break;
		dirid= pb.d.ioDrParID;
	}
	return next;
}

void
fullpath(buf, wdrefnum, file)
	char *buf;
	int wdrefnum;
	char *file;
{
	strcpy(buf, getdirname(wdrefnum));
	strcat(buf, file);
}

--
Guido van Rossum, Centre for Mathematics and Computer Science (CWI), Amsterdam
guido@piring.cwi.nl or mcvax!piring!guido or guido%piring.cwi.nl@uunet.uu.net