thread-safe access action item

Here are my proposed additions to the techniques document in response to my
action item involving thread-safe access additions to the techniques
document. Note: we might consider this type of wording for any
interoperable API technique.

Technique section 6.1 DOM Read Access:

Add Note 3. under Notes and Rationale

3. Providers of programmatic access to the DOM must do so in a thread-safe
manner to ensure that application and system are not compromised. In
multi-threaded environments assistive technologies will access the DOM in
or out of process but on a separate thread. If more than on thread is
accessing the DOM at the same time its integrity cannot be guaranteed
resulting in deadlock situations and memory access violations corrupting
the application and possibly the assistive technology. The use of common
operating system supported intertask communication features such as
semaphores to ensure mutually exclusive access to the DOM should be
employed to ensure synchronized thread-safe access.

Technique section 6.2 DOM Write Access:

Add Note 4. under Notes and Rationale

4. Providers of programmatic access to the DOM must do so in a thread-safe
manner to ensure that application and system are not compromised. In
multi-threaded environments assistive technologies will access the DOM in
or out of process but on a separate thread. If more than on thread is
accessing the DOM at the same time its integrity cannot be guaranteed
resulting in deadlock situations and memory access violations corrupting
the application and possibly the assistive technology. The use of common
operating system supported intertask communication features such as
semaphores to ensure mutually exclusive access to the DOM should be
employed to ensure synchronized thread-safe access.

Rich Schwerdtfeger
Senior Technical Staff Member
IBM Accessibility Center
Research Division
EMail/web: schwer@us.ibm.com

"Two roads diverged in a wood, and I -
I took the one less traveled by, and that has made all the difference.",
Frost

Received on Thursday, 18 April 2002 14:12:15 UTC