request for thread safety advice View as Markdown

nice for that would be some macros (somewhere in zend????) which help in
the following way (the ext_skel should generate the code, too):

a) define a global library identifier (for all blocks that should not run
at the same time)
zend_create_mutex(identifier)

b) use some code like:
zend_start_synchronized(identifier) {
...
...
} zend_end_synchronized(identifier);

(Same construct like zend_try). Without ZTS this macros should be empty...

As I am the developer of the NSAPI SAPI (which runs only with ZTS) I would
like to have a GD extension where alle PHP_FUNCTIONs exported from there
should have such Java-like "synchronized" blocks.

Uwe

At 00:10 21.10.2003, you wrote:

If the library you are wrapping is not threadsafe, one approach is to
simply not worry about it and just mark your extension as not being safe
to use in a threaded environment. The majority of people use PHP in a
non-threaded environment anyway.

If you want to be nice to the folks who do use PHP in a threaded
environment, you can look into adding a semaphore lock around the calls
into the code that is not threadsafe. Such a semaphore lock makes sure
that only 1 thread at a time can enter the code. Other threads sit around
and wait until it is their turn.

-Rasmus

Hi, internals.

Please send me (post here i mean) a few links about

1. thread safety in general
2. thread saftey in php
3. I'm doing wrapper for librep wich is not thread
   safe (so mailing archives say). Do I need to know
   something special ?

After doing some googling i found thise for #1
http://www.unix.org/version2/whatsnew/threads.html
http://www.unix.org/version2/whatsnew/threadsref.html
is that a good reading ?

any better suggestions for google requests than thise :
c thread safety -mail -archive -lists
c thread safety tutor
?

I couldn't find anything for #2 but it's not less
important than #1 :)

--

Uwe Schindler
thetaphi@php.net - http://www.php.net
NSAPI SAPI developer
Erlangen, Germany