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<channel>
	<title>狗爺語錄</title>
	
	<link>http://me.abelcheung.org</link>
	<description>吠盡不平事</description>
	<pubDate>Sun, 28 Sep 2008 22:28:44 +0000</pubDate>
	<generator>http://wordpress.org/?v=2.6.2</generator>
	<language>en</language>
			<atom10:link xmlns:atom10="http://www.w3.org/2005/Atom" rel="self" href="http://feeds.feedburner.com/abelcheung" type="application/rss+xml" /><item>
		<title>投票：Windows 版的 PHP 是甚麼？</title>
		<link>http://me.abelcheung.org/2008/09/19/%e6%8a%95%e7%a5%a8%ef%bc%9awindows-%e7%89%88%e7%9a%84-php-%e6%98%af%e7%94%9a%e9%ba%bc%ef%bc%9f/</link>
		<comments>http://me.abelcheung.org/2008/09/19/%e6%8a%95%e7%a5%a8%ef%bc%9awindows-%e7%89%88%e7%9a%84-php-%e6%98%af%e7%94%9a%e9%ba%bc%ef%bc%9f/#comments</comments>
		<pubDate>Thu, 18 Sep 2008 18:13:17 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Software]]></category>

		<category><![CDATA[Web]]></category>

		<category><![CDATA[PHP]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=566</guid>
		<description><![CDATA[<ol>
<li>玩具</li>
<li>垃圾</li>
</ol>
<p>沒有第三個選擇。</p>
]]></description>
		<wfw:commentRss>http://me.abelcheung.org/2008/09/19/%e6%8a%95%e7%a5%a8%ef%bc%9awindows-%e7%89%88%e7%9a%84-php-%e6%98%af%e7%94%9a%e9%ba%bc%ef%bc%9f/feed/</wfw:commentRss>
		</item>
		<item>
		<title>Protected: 使用 Consolas 字體</title>
		<link>http://me.abelcheung.org/2008/09/16/%e4%bd%bf%e7%94%a8-consolas-%e5%ad%97%e9%ab%94/</link>
		<comments>http://me.abelcheung.org/2008/09/16/%e4%bd%bf%e7%94%a8-consolas-%e5%ad%97%e9%ab%94/#comments</comments>
		<pubDate>Tue, 16 Sep 2008 14:40:15 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Windows]]></category>

		<category><![CDATA[fonts]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=559</guid>
		<description><![CDATA[There is no excerpt because this is a protected post.]]></description>
		<wfw:commentRss>http://me.abelcheung.org/2008/09/16/%e4%bd%bf%e7%94%a8-consolas-%e5%ad%97%e9%ab%94/feed/</wfw:commentRss>
		</item>
		<item>
		<title>The crown jewel of over-engineering</title>
		<link>http://me.abelcheung.org/2008/09/04/the-crown-jewel-of-over-engineering/</link>
		<comments>http://me.abelcheung.org/2008/09/04/the-crown-jewel-of-over-engineering/#comments</comments>
		<pubDate>Wed, 03 Sep 2008 17:26:21 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Blog]]></category>

		<category><![CDATA[Software]]></category>

		<category><![CDATA[WordPress plugin]]></category>

		<category><![CDATA[硬膠]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=557</guid>
		<description><![CDATA[<p>If there is a warning message shown inside WordPress admin interface, I&#8217;m not quite sure what I would do (maybe directly modify the code to disable it); but this certain guy provides a brilliant ingenious solution.</p>
<blockquote style="font-size: larger"><p><a target="_blank" href="http://wordpress.org/extend/plugins/dashboard-fixer/">Write a complete PHP class as a WordPress plugin to hide the message!</a></p></blockquote>
<p>Not to mention it just <strong>hides message</strong> without fixing the problem!</p>
<p>Oh yeah, and it even clearly states that the problem appears in WordPress 2.5.0 <strong>only</strong>, which is fixed in 2.5.1.</p>
<p>Hmm, did I forgot to emphasize this error message is shown in <strong>admin interface only</strong>, but not in public viewable pages?</p>
<p>Don&#8217;t underestimate people&#8217;s creativity.</p>
]]></description>
		<wfw:commentRss>http://me.abelcheung.org/2008/09/04/the-crown-jewel-of-over-engineering/feed/</wfw:commentRss>
		</item>
		<item>
		<title>搜狗百度，我愛死你們了！</title>
		<link>http://me.abelcheung.org/2008/08/29/%e6%90%9c%e7%8b%97%e7%99%be%e5%ba%a6%ef%bc%8c%e6%88%91%e6%84%9b%e6%ad%bb%e4%bd%a0%e5%80%91%e4%ba%86%ef%bc%81/</link>
		<comments>http://me.abelcheung.org/2008/08/29/%e6%90%9c%e7%8b%97%e7%99%be%e5%ba%a6%ef%bc%8c%e6%88%91%e6%84%9b%e6%ad%bb%e4%bd%a0%e5%80%91%e4%ba%86%ef%bc%81/#comments</comments>
		<pubDate>Thu, 28 Aug 2008 18:53:23 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Web]]></category>

		<category><![CDATA[search engine]]></category>

		<category><![CDATA[硬膠]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=554</guid>
		<description><![CDATA[<p>這是搜狗上個月為我提供 7 倍 (!) 流量的回禮：</p>
<div id="attachment_556" class="wp-caption aligncenter" style="width: 310px"><a href="http://me.abelcheung.org/wp-content/uploads/2008/08/my-site-in-sogou.png" rel="lightbox"><img src="http://me.abelcheung.org/wp-content/uploads/2008/08/my-site-in-sogou-300x109.png" alt="我的站目前在搜狗的搜尋結果" title="我的站目前在搜狗的搜尋結果" width="300" height="109" class="size-medium wp-image-556" /></a><p class="wp-caption-text">我的站目前在搜狗的搜尋結果</p></div>
<div id="attachment_555" class="wp-caption aligncenter" style="width: 310px"><a href="http://me.abelcheung.org/wp-content/uploads/2008/08/my-site-in-baidu.png" rel="lightbox"><img src="http://me.abelcheung.org/wp-content/uploads/2008/08/my-site-in-baidu-300x87.png" alt="我的站目前在百度的搜尋結果" title="我的站目前在百度的搜尋結果" width="300" height="87" class="size-medium wp-image-555" /></a><p class="wp-caption-text">我的站目前在百度的搜尋結果</p></div>
]]></description>
		<wfw:commentRss>http://me.abelcheung.org/2008/08/29/%e6%90%9c%e7%8b%97%e7%99%be%e5%ba%a6%ef%bc%8c%e6%88%91%e6%84%9b%e6%ad%bb%e4%bd%a0%e5%80%91%e4%ba%86%ef%bc%81/feed/</wfw:commentRss>
		</item>
		<item>
		<title>Pwnie award</title>
		<link>http://me.abelcheung.org/2008/08/22/pwnie-award/</link>
		<comments>http://me.abelcheung.org/2008/08/22/pwnie-award/#comments</comments>
		<pubDate>Thu, 21 Aug 2008 22:39:00 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Blog]]></category>

		<category><![CDATA[Security]]></category>

		<category><![CDATA[buggy software]]></category>

		<category><![CDATA[PHP]]></category>

		<category><![CDATA[vulnerability]]></category>

		<category><![CDATA[WordPress]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=548</guid>
		<description><![CDATA[<p>真是不知這個用中文怎樣說，「千瘡百孔泛黑大獎」也不足言其英文含意之萬一。<a target="_blank" href="http://pwnie-awards.org/2008/awards.html#mass0wnage">給 WordPress 的這個獎</a>姍姍遲來，對我而言有點遲過頭了，雖然總好過沒有。但頒這個獎也是實情。君不見在 SecurityFocus 個個星期它都榜上有名！還要個個大鑊，即使不是 WordPress 本身，也是一些很多人用的 plugin 漏洞引致整個 blog 內爆。淨是旁邊的 blog list，近期也有一個被黑了，另一個被嚇得急急更新。</p>
<p>還<a target="_blank" href="http://blog.taragana.com/index.php/archive/wordpress-wins-pwnie-award-for-mass-0wnage-for-many-many-security-vulnerabilities/">想 WordPress 做 audit</a> 的真在太妄想，至少<a target="_blank" href="http://comox.textdrive.com/pipermail/wp-forums/2006-March/001532.html">兩年半前投訴</a>到現在，要做的早做了。phpNuke，phpBB，WordPress 這老中青三代都該永久擁有這個獎，以誌它們將 OSS 的 <a target="_blank" href="http://www.dwheeler.com/secure-programs/Secure-Programs-HOWTO/open-source-security.html">many eyeball theory</a> 徹底推翻。</p>
]]></description>
		<wfw:commentRss>http://me.abelcheung.org/2008/08/22/pwnie-award/feed/</wfw:commentRss>
		</item>
		<item>
		<title>吹爆餿狗大行動</title>
		<link>http://me.abelcheung.org/2008/08/19/%e5%90%b9%e7%88%86%e9%a4%bf%e7%8b%97%e5%a4%a7%e8%a1%8c%e5%8b%95/</link>
		<comments>http://me.abelcheung.org/2008/08/19/%e5%90%b9%e7%88%86%e9%a4%bf%e7%8b%97%e5%a4%a7%e8%a1%8c%e5%8b%95/#comments</comments>
		<pubDate>Tue, 19 Aug 2008 15:48:53 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Site maintenance]]></category>

		<category><![CDATA[Web]]></category>

		<category><![CDATA[user agent]]></category>

		<category><![CDATA[web server]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=546</guid>
		<description><![CDATA[<p><a href='http://me.abelcheung.org/wp-content/uploads/2008/08/blow.png' rel='lightbox'><img src="http://me.abelcheung.org/wp-content/uploads/2008/08/blow-150x150.png" alt="我要吹爆你呀！" title="我要吹爆你呀！" width="150" height="150" class="alignright" /></a></p>
<p>竟然<a href="http://me.abelcheung.org/2008/08/02/%e6%90%9c%e7%8b%97%e5%a4%a7%e5%8f%8d%e6%93%8a/#comment-91982">這麼快就說</a>上次的 iptables rule 太絕了？那些規則用了不到三天就不用了！何解？</p>
<ol>
<li>餿狗實在太自私兼聰明了，發覺一段短時間沒有 traffic，它就會自行中斷連線；拖字訣對它完全無效。相反地，百度反而有用，一直都是等很多分鐘才 timeout。</li>
<li>近來開始做一些網站統計分析，但這些賤種搜尋引擎對於 traffic 的統計百害而無一利，所以要想個辦法將它永遠趕走，淨是 timeout 還是不太夠。</li>
</ol>
<p>第二個階段，嘗試讓它們自家打自家：用 Apache 的 RewriteRule，將百度的 request redirect 去餿狗，再將餿狗的 request 丢到百度去，因為它們互為天敵，所以看到我煽風點火，理應不再管我才是。結果我猜錯了，還是陸續有來，餿狗最高每 3-5 秒一次，百度最高速度也有 3-5 分鐘，而且仍是拼命找我禁止 index 的地方。</p>
<p>最後按捺不住了，出最後的殺手鐧，找專人侍候它們。</p>
<p><code>iptables -t nat -A PREROUTING -j DNAT -p tcp -s 220.181.0.0/16 --dport 80 --to-destination :81</code></p>
<p>這些搜尋引擎絕對值得我另開渠道去服侍。服侍它們的僕人來頭可不少：<code>/dev/urandom</code> <img src='http://me.abelcheung.org/wp-includes/images/smilies/icon_biggrin.gif' alt=':D' class='wp-smiley' /> </p>
<p>當然，一開始就給它們下馬威不是太禮貎，怕太快會嚇怕它們。所以提供一個正常的 HTTP header 作為甜頭是必須的：</p>
<blockquote>
<pre>
<code>
#!/bin/sh

sleep 5
cat &lt;&lt; _EOF_
HTTP/1.1 200 OK
Date: `date +"%a, %d %b %Y %H:%M:%S HKT"`
Server: Apache/2.0
Transfer-Encoding: chunked
Content-Type: text/html

_EOF_

<strong>exec cat &lt; /dev/urandom</strong>
</code>
</pre>
</blockquote>
<p>結果？餿狗好像不是太喜歡我的待客態度！現在連踪影都沒了，真是有點懷念餿狗的日子啊！至少不會那麼無聊。現在要應付的可麻煩多了，因為近來發覺有不少都是扮假狗，模彷 IE 的 user agent 的，雖然有些仍然找到別的蛛絲馬跡。例如有一個雖然是扮 IE，但是使用 HTTP/1.0，而且快速存取大量全無關係的頁面的。</p>
]]></description>
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		</item>
		<item>
		<title>大石砸不死蟹：咖啡店</title>
		<link>http://me.abelcheung.org/2008/08/14/%e5%a4%a7%e7%9f%b3%e7%a0%b8%e4%b8%8d%e6%ad%bb%e8%9f%b9/</link>
		<comments>http://me.abelcheung.org/2008/08/14/%e5%a4%a7%e7%9f%b3%e7%a0%b8%e4%b8%8d%e6%ad%bb%e8%9f%b9/#comments</comments>
		<pubDate>Wed, 13 Aug 2008 18:53:44 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Life]]></category>

		<category><![CDATA[coffee]]></category>

		<category><![CDATA[gossip]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=524</guid>
		<description><![CDATA[<p>當知道 Starbucks 美國的業務萎縮時，我和<a target="_blank" href="http://www.reuters.com/article/oddlyEnoughNews/idUSN0739957520080707">很多人的意見一樣</a>，都很高興見到它萎縮，而且是希望香港的業務都能萎縮一下（雖然好像沒那個跡象）。自從幾年前，就喜歡喝咖啡，雖然到現在還是不懂分辨種類、分辨甚麼才能稱為好的咖啡，但在 café 中，享受那片刻寧靜，也是重要的元素之一。</p>
<p>可是在今時今日，不論是 Starbucks 還是 Pacific Coffee，都不再有那回事，不是一家大小擾擾攘攘，就是成堆的中學生當 café 是自己家一樣嚷個不停，再不然就是像去飲茶般和大羣人爭位坐，總之到那種地方等於和自己過不去，毫無半點享受可言。（每次星期六去又一城那間 Pacific Coffee 都是惡夢。）剩下比較舒服的，就只有中環、灣仔等商業區一些比較冷僻的位置開的 café，而且要選在星期六下午，已經沒有人會上班的時間，更不能接近購物商場。諷刺的是這些 café 很多都做不長久，小本經營的尤甚，因為大部份都會被大財團那些打沉。</p>
<p>雖然 Starbucks 帶來了那種「咖啡文化」，但也同時親手扼殺了它，因為它不只是一杯咖啡那麼簡單，也要講格調、講環境的。現在去那些喧哇 café 就等於去麥當努吃快餐，快快喝完快快走（別說 McCafe 了，雖然有時時間所限，沒有別的地方可以去）。Pacific Coffee <a target="_blank" href="http://space.zkiz.com/-38-viewspace-2388.html">早已風光不再</a>，如果 Starbucks 在香港也一樣消沉下去，讓小本生意的 café 有多點生存空間，那對我來說絕對是一椿好事。</p>
<p>暫時還是大家樂/美心那些幾元一杯的就算了，反正不會考慮舒服甚麼的了。自己沖的總是不行。</p>
]]></description>
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		</item>
		<item>
		<title>So long, Quarry</title>
		<link>http://me.abelcheung.org/2008/08/12/so-long-quarry/</link>
		<comments>http://me.abelcheung.org/2008/08/12/so-long-quarry/#comments</comments>
		<pubDate>Tue, 12 Aug 2008 13:29:24 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Fun &amp; Games]]></category>

		<category><![CDATA[Software]]></category>

		<category><![CDATA[board game]]></category>

		<category><![CDATA[Chess]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=531</guid>
		<description><![CDATA[<p><a target="_blank" href="https://mail.gna.org/public/quarry-dev/2008-07/msg00001.html">安息吧。</a></p>
<p>總覺得有點可惜，因為 <a target="_blank" href="http://home.gna.org/quarry/index.html">Quarry</a> 是我見過的棋盤中寫得比較好的（對用家來說，不是裏面的 code），而且可以作為多種棋盤使用。圍棋可以用 gnugo 和人對戰，也可以兩個 gnugo 自己來，更可以人手編輯棋局；蘋果棋（黑白棋）則有 grhino，一樣地使用。</p>
<table>
<tr>
<td>
<a target="_blank" href="http://farm4.static.flickr.com/3237/2724940664_fd86ef1aee_o.png" rel="lightbox" title="Go board mode"><img src="http://farm4.static.flickr.com/3237/2724940664_5ec74ff34d_t.jpg" alt="Quarry: screenshot for Go (game start)" width="100" height="69" /></a>
</td>
<td>
<a target="_blank" href="http://farm4.static.flickr.com/3252/2724116807_7ced32817e_o.png" rel="lightbox" title="Reversi board mode"><img src="http://farm4.static.flickr.com/3252/2724116807_ede378d564_t.jpg" alt="Quarry: screenshot for Reversi" width="100" height="69" border="0" /></a>
</td>
</tr>
</table>
<p><strike>
<p>但我不知為何作者不在網站中聲明自己已經放棄維護它，現在的網站有點誤導，令人以為它還有 0.3 版本。 <img src='http://me.abelcheung.org/wp-includes/images/smilies/icon_sad.gif' alt=':-(' class='wp-smiley' /> </p>
<p></strike></p>
<p><small>2008-08-16 編輯：還以為 Quarry maintainer 沒理我，原來是我的郵件未通過 mailing list，怪不得沒反應。現在網站上已經反映實際情況了。</small></p>
]]></description>
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		</item>
		<item>
		<title>WordPress plugin: 密碼提示</title>
		<link>http://me.abelcheung.org/2008/08/11/wordpress-plugin-%e5%af%86%e7%a2%bc%e6%8f%90%e7%a4%ba/</link>
		<comments>http://me.abelcheung.org/2008/08/11/wordpress-plugin-%e5%af%86%e7%a2%bc%e6%8f%90%e7%a4%ba/#comments</comments>
		<pubDate>Mon, 11 Aug 2008 00:10:40 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Blog]]></category>

		<category><![CDATA[Coding]]></category>

		<category><![CDATA[WordPress plugin]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=544</guid>
		<description><![CDATA[<p>反正是睡不着，所以快手地寫了個甚為簡單的 WordPress plugin，是在有密碼保護的文章中加上密碼提示的。之前嘗試貼出有密碼保護的文章時，要在另一個 post 給予提示，頗為不方便。這個 plugin 已經想做很久了，但一直沒有下定決心，趁這點點空閒寫了出來，<a href="http://me.abelcheung.org/devel/protected-post-password-hint/">放了在自己的站上</a>。有興趣的可以看看，很易用的，不需要甚麼設定。</p>
]]></description>
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		<title>Another Kakuro strategy: difference of 2 cells</title>
		<link>http://me.abelcheung.org/2008/08/09/kakuro-strategy-difference-of-2-cells/</link>
		<comments>http://me.abelcheung.org/2008/08/09/kakuro-strategy-difference-of-2-cells/#comments</comments>
		<pubDate>Sat, 09 Aug 2008 01:07:25 +0000</pubDate>
		<dc:creator>Abel</dc:creator>
		
		<category><![CDATA[Fun &amp; Games]]></category>

		<category><![CDATA[kakuro]]></category>

		<guid isPermaLink="false">http://me.abelcheung.org/?p=534</guid>
		<description><![CDATA[<p>Last time I have had discussed about using arithmetics to solve kakuro (<a href="http://me.abelcheung.org/2008/02/19/solving-kakuro-1/">part 1</a>, <a href="http://me.abelcheung.org/2008/02/29/solving-kakuro-2/">part 2</a>); most of the methods are trivial for everybody except the last case which is not apparent. This one is also not apparent as well, and I have almost <strong>never</strong> encountered it except once. It is about:</p>
<blockquote><p>Calculating the <strong>difference</strong> between 2 cells!</p></blockquote>
<p>How can the <em>difference</em> of 2 cells be helpful? See below for initial configuration:</p>
<p><!--more--></p>
<p><img src="http://me.abelcheung.org/wp-content/uploads/2008/08/kakuro-sample-1.png" alt="Kakuro initial configuration" title="Kakuro initial configuration" width="272" height="272" /></p>
<p>It is an open end layout, so using addition and subtraction seems not very feasible. There is also no apparent target with only one possible answer. Actually there is, but very well hidden. Calculate the sum of digits marked with green and red:</p>
<table>
<tr>
<td>
<a href='http://me.abelcheung.org/wp-content/uploads/2008/08/kakuro-sample-2.png' title='kakuro step 1 (vertical)' rel='lightbox[kakuroinitialstep]'><img src="http://me.abelcheung.org/wp-content/uploads/2008/08/kakuro-sample-2-150x150.png" alt="kakuro step 1 (vertical)" title="kakuro step 1 (vertical)" width="150" height="150" /></a>
</td>
<td>
<a href='http://me.abelcheung.org/wp-content/uploads/2008/08/kakuro-sample-3.png' title='kakuro step 1 (horizontal)' rel='lightbox[kakuroinitialstep]'><img src="http://me.abelcheung.org/wp-content/uploads/2008/08/kakuro-sample-3-150x150.png" alt="kakuro step 1 (horizontal)" title="kakuro step 1 (horizontal)" width="150" height="150" /></a>
</td>
</tr>
</table>
<p>Take the difference between red and green areas. The result is the difference of the 2 squares marked A and B, which is 4 ( = 38 - 34 ) :</p>
<p><img src="http://me.abelcheung.org/wp-content/uploads/2008/08/kakuro-sample-4.png" alt="kakuro step 2" title="kakuro step 2" width="272" height="272" /></p>
<p>So? There are still too many choices, 4 can be 5-1, can be 6-2, …… The key point is, only one of the choices is possible! Notice the 3rd row (with sum equal to 22), there are only 2 possible combinations, namely (5,8,9) and (6,7,9).</p>
<ol>
<li>B-A=4 ⇒ A ≤ 5</li>
<li>From the 2 decompositions of 22 ⇒ A ≥ 5</li>
</ol>
<p>Bingo! (A,B) = (5,9).</p>
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