How to implement a "mutex" lock

Hi there, I'm in a need of creating something like a mutex mechanism, not related to a table.
Is it possible or do I have to fill in any dummy table ?
Cheers,
Bart

Hi,
The status monitor for the integrated ITS (transaction SITSPMON) is used to display the current status of the integrated ITS functionality in the application server. You can display and change the currently set parameters. You can get information on the memory load, on the content of the ITS caches, on set locks and on activated features.
Functions
The different pieces of information displayed on the screen are sorted by categories, which you can view using the respective tabstrip. Currently, the following display screens are available:
·        Parameters
·        Memory Statistics
·        Template and MIME Cache
·        Mutex Locks
·        HTML Template Directory
·        Feature List
Mutex Locks
Mutex Locks (Mutual Exclusions) prevent competing access to resources. The integrated ITS function uses mutex locks for the HTML template cache, which exists only once for all work processes, to prevent the situation that a work process stores a new HTML template version in the HTML template cache while another work process processes an HTML template.
Apart from this, mutex locks are used for
·        Memory statistics
·        Individual HTML template cache entries
·        HTML Template Directory
Try exploring how this functionality have been done in transaction SITSPMON.
Regards,
Harish

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I think that this link can help you
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totally plagiarized from expert oracle database architecture 9i, 10g, 11g by Tom Kyte pg201
one popular implementation of optimistic locking is to keep the old and new values in the application and upon updating the data use and update like this
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where primary_key = :primary_key
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every time a row is modified.
another one on page 204
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the ones suggested where owa_opt_lock.checksum, dbms_obfuscation_toolkit.md5, dbms_crypto.hash, ora_hashEdited by: pollywog on Nov 17, 2010 3:48 PM
might be a good book for you to look into getting it has a whole chapter on locking and latching.
Edited by: pollywog on Nov 17, 2010 3:54 PM

Implementing "critical sections" using recursive mutex locks

Greetings.
I have chosen pthread mutexes for implementing critical sections in my ported Windows code. As you probably all know, mutexes do not by default support recursive locking and will deadlock if attempted. With Solaris 7 came support for recursive locking through the PTHREAD_MUTEX_RECURSIVE type of mutex. The problem I have encountered when using these recursive mutexes doesn't even involve recursive locking, yet only manifests itself when using the recursive type.
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Should I be able to see a priority change using a mutex lock ?

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On one scenario we are running our application
On a v245 running Solaris 10 6/06 update 2 patch 118833-24
On our 5120 we are running Solaris 10 8/07 update 4patch 137111-05.
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On edit: How do you know that pthread_mutex_destroy() is not destroying the mutex?
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How to implement a "mutex" lock

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