NAME
    CurrentDir -- Make a directory lock the current directory

SYNOPSIS
    oldLock = CurrentDir( lock )
    D0                    D1

    BPTR CurrentDir(BPTR)

FUNCTION
    CurrentDir() causes a directory associated with a lock to be made
    the current directory.  The old current directory lock is returned.

    A value of zero is a valid result here, this 0 lock represents the
    root of file system that you booted from.

    Any call that has to Open() or Lock() files (etc) requires that
    the current directory be a valid lock or 0.

INPUTS
    lock - BCPL pointer to a lock

RESULTS
    oldLock - BCPL pointer to a lock

SEE ALSO
    Lock(), UnLock(), Open(), DupLock()