From: zabmilenko at charter dot net
Operating system: WinXP
PHP version: 5.1.2
PHP Bug Type: Feature/Change Request
Bug description: Block-level Semaphore Locking
Description:
------------
Currently, the sysvsem library is used for semaphore locking. I am
proposing to integrate this functionality directly into php using a
block-level statement:
sem (420)
{
// Locked stuff here
}
The idea is that any code present inside the sem{} block will be
guaranteed by php to be executed alone. 420 is the lock to set or wait
for. Execution can be halted before the end of the sem block using the
break; statement, as well as return, die, exit, or any other statement
that moves execution outside of the block. As soon as execution leaves,
the semaphore is instantly released.
Naturally, nesting a lock is redundant but nevertheless could serve a
purpose. If a nested lock is detected, a warning should be generated.
This functionality would be minimalistic, but powerful and elegant when
compared to the sysvsem library. If your imagination is wandering, then a
radical idea would be setting a timeout or even a lock-count limit using
parameters separated by ; (like a for() block).
Anyways, my suggestion is a sem block. Have a nice day.
Reproduce code:
---------------
sem (0x2243)
{
// open a file
// write a line
// close the file
}
Expected result:
----------------
The first process will lock semaphore 0x2243 and attempt to write a line
to a file. Any concurrent attempts will be delayed until the first
process reaches leaves the sem block.
Actual result:
--------------
I get a parse error because my idea is still only in my head.
--
Edit bug report at http://bugs.php.net/?id=36541&edit=1
--
Try a CVS snapshot (PHP 4.4):
http://bugs.php.net/fix.php?id=36541&r=trysnapshot44
Try a CVS snapshot (PHP 5.1):
http://bugs.php.net/fix.php?id=36541&r=trysnapshot51
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=36541&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=36541&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=36541&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=36541&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=36541&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=36541&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=36541&r=support
Expected behavior: http://bugs.php.net/fix.php?id=36541&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=36541&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=36541&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=36541&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=36541&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=36541&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=36541&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=36541&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=36541&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=36541&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=36541&r=mysqlcfg
