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CBL_MONITOR_OPEN_INTRA

Creates a monitor synchronization object for thread synchronization within one process.
Note: This routine is not supported in JVM COBOL.

Syntax:

call "CBL_MONITOR_OPEN_INTRA" using by reference monitor-handle
                              by value           open-flags

Parameters

  Using call prototype (see Key) Picture
monitor-handle cblt-pointer usage pointer.
open-flags cblt-os-flags pic x(4) comp-5

or

pic x(8) comp-5 (64-bit native programs only)

On Entry:

open-flags
A value indicating the priority algorithm used to grant locks:
Bit 0
0 Readers and writers have interleaved priority; that is, if a write request is issued, any further read requests will block until the first write request is granted and finished
1 Read requests always have priority, possibly leading to writer starvation.
Remaining bits
Reserved and should be set to zero.

On Exit:

monitor-handle
The monitor handle.
return-code
A value of 0 indicates that the call was successful. Any other value indicates an error. See RETURN-CODE Values For Synchronization Routines.

Comments:

If open-flags bit 0 is set to 0, and nested read locks are requested, then single thread deadlock is possible.

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