NetWare 4.1/9000 Concepts

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NetWare Glossary
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When a NetWare client tries to lock a file, NetWare first makes sure that the
lock request does not conflict with other NetWare locks. If it does not,
NetWare attempts to lock the entire file under UNIX.
If any UNIX locks are on the file, the lock request fails. Many NetWare
clients can set locks on the file or many UNIX processes can set locks on the
file, but not both concurrently.
NetWare allows shareable and exclusive locks on files opened in read-only
or read-write mode, but UNIX allows shareable and exclusive locks only
when a file is opened in read-write mode.
If the UNIX file is opened in read-only mode, only shareable UNIX locks
can be applied. If the UNIX file is opened write-only, only exclusive UNIX
locks can be applied.
Therefore, to allow maximum interoperability between NetWare and UNIX,
NetWare always opens files in read-write mode.
UNIX locks are only advisory; UNIX does not enforce them. Applications
are responsible for checking locks and enforcing them.
UNIX operating system
A computer operating system originally developed at Bell Labs in 1969.
UNIX features include
• Multiuser functionality
• Multitasking
• Platform independence
• Built-in communication tools
• Application portability
• Password and file access security
See also: “HP-UX.”