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Inside Macintosh: Files /

Chapter 2 - File Manager / File Manager Reference

Low-Level Volume Access Routines / Mounting and Unmounting Volumes

PBMountVol

You can use the PBMountVol function to mount a volume.

FUNCTION PBMountVol (paramBlock: ParmBlkPtr): OSErr;

paramBlock

A pointer to a basic FIle Manager parameter block.

<--	ioResult	OSErr	The result code of the function.
<->	ioVRefNum	Integer	On input, a drive number. On output, the volume reference number.

DESCRIPTION

The PBMountVol function mounts the volume in the specified drive. If there are no volumes already mounted, this volume becomes the default volume.

Because you specify the volume to be mounted by providing a drive number, you can use PBMountVol to mount only one volume per disk.

The PBMountVol function always executes synchronously.

Note

The PBMountVol function opens two files needed for maintaining
file catalog and file mapping information. If no access paths are available for these two files, PBMountVol fails and returns tmfoErr
as its function result.

ASSEMBLY-LANGUAGE INFORMATION

The trap macro for PBMountVol is _MountVol.

RESULT CODES

noErr	0	No error
ioErr	-36	I/O error
tmfoErr	-42	Too many files open
paramErr	-50	Bad drive number
volOnLinErr	-55	Volume already online
nsDrvErr	-56	No such drive
noMacDskErr	-57	Not a Macintosh disk
extFSErr	-58	External file system
badMDBErr	-60	Bad master directory block
memFullErr	-108	Not enough room in heap zone