The problem with C's volatile qualifier
The real problem with C's volatile (well, one of them) is that volatile only affects the compiler; it doesn't normally make thecompiler do anything to affect the CPU's interaction with memory. Onmodern hardware, merely affecting the compiler is not enough; theCPU/memory interface has its own optimizations, which must be dealt withtoo for shared-state code to work right.
From the perspective of history this makes a lot of sense, becauseANSI C mostly predates CPU memory controllers
獨手
我因為打足球打斷了左手的手腕骨
做了一個月獨臂少年
今日
我因為打電腦過多
右手手腕勞損
手指不能動
不能用力
不能做任何動作
再度成為獨臂人
勁唔方便
二十年來
我做任何事都靠這隻右手
今日連刷牙都冇力
褲鍊都冇力拉
My current views on webmail providers
I have come to a grumpy realization recently:
Unsecured webmail systems are today's open SMTP relays, and it'shigh time that they got treated the same way.
The comparison is all the more striking because (once) major ISPsappear to have decided that they can run open webmail systemswithout consequences, much as people once shrugged off runningopen SMTP relays.
(I am particularly depressed by the move of places like rr.com,comcast.net, and adelphia.net into webmail systems that are
2006大事回顧 (其實係私事)
2. 做o左Lasik。雖然有後遺症，反反覆覆都好唔到，甚至將來可能連身邊最親既人既樣都望唔清。但係，我冇
Link: Threads Cannot be Implemented as a Library
I've already linked to this in passing , but I'm going to rerun itas an explicit link. Threads Cannot be Implemented as a Library by HansBoehm makes the argument in its title:
We provide specific arguments that a pure library approach, in whichthe compiler is designed independently of threading issues, cannotguarantee correctness of the resulting code.
There is also a discussion of this paper at Lambda the Ultimate that may be interestingreading. On a quick skim of the LtU discussion thread, thisUsenet article
Solaris's impressive ABI compatibility
There are some things that Solaris is very good at; one of them isuser-level ABI compatibility (at least for basic programs). As anillustration of just how good it is, I only recently noticed that on ourSolaris 8 machines I am still routinely using some dynamically linkedprograms compiled in August of 1993 (which is probably when this groupstarted using Solaris machines).
I hadn't noticed before now because the programs hadn't really changedsince then (so I had no
2007，點搞都得
新的一年
第一件事是想一想這個blog的去向
有沒有發現
曾經熱心寫blog的許多朋友
現在更新的速度大不如前
在網誌熱潮最盛時
人人都開一個blog
大家開開心心寫了幾個月
可能漸漸會覺得無事可記
讀者流失
熱情減退
最重要是這件事被主流
A (Solaris 8) automounter irritation
Here's an automounter irritation that keeps biting us: on fileservers,the Solaris 8 automounter is not smart enough to notice when anunderlying If it gets a request for the filesystem, it 'mounts' things anyways,which then fouls up various aspects of, say, remounting the realfilesystems. It is remarkably difficult to persuade the automounter tolet go so that you can restore things to normality, and you can't justshoot the entire automounter The SMTP frontend died twice late Friday night, to my irritation.That said, this week we: The message count is down dramatically from last week because this week /export/
Weekly spam summary on December 30th, 2006
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