HSetVol Select a default default volume/directory (HFS only)

#include <Files.h> File Manager (PBxxx)

OsErr HSetVol( volName, vRefNum, dirID );

Str255 volName; partial or full pathname to set default directory to

short vRefNum; reference number of volume to set default to

long dirID; directory ID of volume to set default to

returns Error Code; 0=no error

Apple does not recommend using HSetVol or PBSetVol. See the notes below

HSetVol is used to select a default volume. The File Manager will use these

defaults in future calls in which you specify no volume name and a volume

Returns: an operating system Error Code. It will be one of:

Notes: You can specify the new default by any of the following options:

• A full or partial pathname (ends in a colon). Put the address of the

• A volume number or a working directory number in ioVRefNum If you use

• A directory number in ioWDDirID (as obtained via PBOpenWD).

See SetVol for an example showing usage of various ways to set a default

HSetVol lets you specify a WDRefNum for the ioVRefNum in addition to a

paritial pathname in ioNamePtr. HSetVol will start at the specified

working directory and use the paritial pathname to determine the final

directory. This directory might not correspond to an already existing

working directory, so the File Manager cannot refer to this directory with a

WDRefNum. Instead it must use the actual volume refNum and the dirID

number (which is assigned when the directory is created, and does not

change). This all means that if you call HSetVol, the File Manager stores

the actual volume refNum as the default volume, and the default dirID

separately. This will happen on all calls to HSetVol. Subsequent calls to

GetVol or PBGetVol or HGetVol will return only the volume refNum in

the ioVRefNum field of the parameter block. If any code tries to use the

refNum returned by GetVol or HGetVol, it will be accessing the root of the

volume, and not the current default directory as expected. This can be

disastrous for desk accessories because they don't know that your code has

called HSetVol or PBGetVol and they don't get what they expect if they call

Because of these problems, Apple does not recommend using HSetVol or