FSpRstFLock
spec is pointer to an FSSpec record specifying the file to be unlocked. Returns: an operating system Error Code. It will be one of:
noErr (0) No error
dirNFErr (-120) Directory not found
extFSErr (-58) External file system
fnfErr (-43) File not found
ioErr (-36) I/O error
nsvErr (-35) No such volume
vLckdErr (-46) Volume is locked
wPrErr (-44) Diskette is write-protected
version of the PBHRstFLock function.