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杂记 20130505

使用tc + netem可以模拟一些网络环境
http://www.linuxfoundation.org/collaborate/workgroups/networking/netem#Delay_distribution
比如我可以让每个包都延迟1秒，某些情况下玩游戏还可以作弊

Google Chrome说Profile无法正确打开： 把配置目录里的'Web Data'目录干掉
http://www.fourleaftechnology.com/index.php/General/google-chrome-profile-could-not-be-opened-correctly-error.html

用gs去除PDF的密码：
http://www.cyberciti.biz/faq/removing-password-from-pdf-on-linux/
gs -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=unencrypted.pdf -c .setpdfwrite -f encrypted.pdf

IE10下如果TTF字体的空格宽度是0，就会无视word-spacing的css规则，不知道是不是IE的bug。

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