HelpPC 2.10	Quick Reference Utility	Copyright 1991 David Jurgens
TC: int unlock( int handle, long offset, long length )        - prototype in io.h        - unlock() removes locks placed on a file region by lock()        - returns 0 on success, else -1 on error        - all locks must be released before program termination        - MS C uses locking()        - see   lock C
Esc or Alt-X to exit	unlock	Home/PgUp/PgDn/End ←↑↓→