FSpSetFLock
FSpSetFLock Lock a file
#include <Files.h> File Manager
FSSpec *spec; a pointer to an FSSpec record
returns Error Code; 0=no error
FSpSetFLock locks a file.
spec is pointer to an FSSpec record specifying the file to be locked.
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

Notes: The FSpSetFLock function locks a file. It is the high-level, FSSpec
version of the PBHSetFLock function.