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  • Is tethering available on GiffGaff Goodybags

    网络上信息丰富,但也滋生以讹传讹。

    GiffGaff Goodybags 能否做 Wi-Fi hotspots (tethering)?我搜来基本都说定量数据套餐的 GiffGaff Goodybags 可以 tethering,无限量数据套餐(12镑/月)不可以 tethering。我当时就对这种说法表示怀疑。

    从情理上说,这可以理解。但从技术上,GiffGaff 如何准确探测 tethering,从而限制 tethering 而不影响正常的手机上网流量,我认为是不可能的。

    或许 GiffGaff 可以从浏览器请求的 header 分辨 mobile browser 还是 desktop browser,但是 header 是可以自定义的,mobile browser 也可以 request desktop site,所以 GiffGaff 不能准确的判断流量来自 tethering 还是手机本身。

    今天,我激活了一张 GiffGaff SIM,£12 Goodybags with unlimited data,然后 tethering 测试了一下网速。结果是 tethering 毫无困难地连上了,上行速度 7.05 Mbps,下行速度 1.33 Mbps,相当不错,比我们家的 ADSL 实际速度还要快很多。

    GiffGaff network speed test
    GiffGaff network speed test
    Home ADSL speed
    Home ADSL speed
    Home ADSL speed test
    Home ADSL speed test
  • Why does screen scroll for no reason?

    近段时间用电脑上网,网页自动滚屏。我以为是无意中打开了 Firefox 自动滚屏的选项,找了一圈,发现 Firefox 确实有此类选项,不过我的 autoscrolling 并未选中,smooth scrolling 倒是选中的。我不清楚它们的区别,不过即使把两个 scrolling 都去除,网页仍在滚屏。后来发现,不光 Firefox 在滚屏,Chrome 也滚屏;LibreOffice 是来回跳屏,PDF Document Viewer 却是正常;打开地址栏下拉列表,立马自动关闭;打开菜单,却是正常。

    Firefox preference for autoscrolling
    Firefox preference for autoscrolling

    我转而搜索电脑无故滚屏或跳动的原因。网上有微弱的线索指向“鼠标滚轮出问题了”。我握在手中的是 Microsoft Wireless Mobile Mouse 3500,我以为是电力不足了。关闭了鼠标电源,问题依旧。

    我再仔细一看,这个电脑上还插着一个 PS2 鼠标,只不过搁置着,把它拔了,一切正常了。

  • Remove php-eaccelerator before updating php 5.3 to 5.4

    今天用 yum update 升级基于 CentOS 的服务器碰到一系列的 errors。

    Yum update errors
    Yum update errors

    我用了 –skip-broken 这个开关,不能解决问题。

    因为 errors 太多,我实在没兴致仔细看,曾经想重装 OS 得了。但终究有一条 error 引起我的注意:

    Error: Package: 1:php-eaccelerator-0.9.6.1-17.el6.remi.x86_64 (@remi)
    Requires: php-common(x86-64) = 5.3.16

    我尝试着卸载了 php-eaccelerator:

    
    yum remove php-eaccelerator
    
    

    然后再升级:

    
    yum update
    
    

    竟然错误没有了。升级成功!

    那就再把 php-eaccelerator 装回去吧。

    
    yum install php-eaccelerator
    
    

    装不上。可能是 remi 的 php 和 epel 的 php-eaccelerator 不兼容吧。

  • OCR in Google Drive

    今天再次惊讶于 Google 的强大。

    在 Google Drive 里打开一个 PDF 文件,是一个类似于 lightbox 效果的在线预览。我今天打开的是一份英文文档扫描后保存为 PDF 的文件,lightbox 里出现的是图像。神奇的是,用鼠标去选中其中某些文字,也能像操作文本文件一样高亮显示选中的部分;更神奇的是,按下 Ctrl+C,再到别处 Ctrl+V,粘贴出来的 OCR 以后的文字。

    PDF 在线预览、图形类似文本的高亮显示、OCR,这三件事情能如此完美的结合在一起,不简单。

  • 空白钢琴谱

    老爸最近爱上钢琴。

    他问我:“能不能打印几张空白钢琴谱给我?”

    我答:“没问题。”

    他又问:“不用我发链接给你吧?网上到处都是。”

    我说:“不用。既然到处都是,那我肯定找得到。“

    于是我就搜索”空白钢琴谱“,”空白钢琴谱 filetype:pdf“,”空白钢琴谱 filetype:doc“,”空白钢琴谱 filetype:docx“,确实很多地方都有,可是都要注册后才能下载,哪怕是免费,我恨注册。就这样找了一圈,还没下载到一个。

    被逼得没办法了,还是不想注册。然后想到,中国的网站就爱让人注册,咱可以找国外的嘛!上 Google Translate,钢琴谱叫 piano sheet music,那就搜”blank piano sheet music filetype:pdf”,一找一个准。

    真是强烈的对比。“自由、分享”,咱中国人热切盼望的,轮到自己能控制“自由、分享”时,自己又在想什么?

    以后不要找了,看这里,免费、免注册下载空白钢琴谱

  • AnTuTu for iPhone

    安兔兔定量分析一个手机的好差,我很喜欢。连测了几个时下和过时的 Android 设备,给我了一个硬件在几年内进步的曲线。

    我又突然想到 Apple 产品所采用的硬件都严重不匹配它的高价,就想安兔兔是不是已有一个 AnTuTu for iPhone 来量化对比一下 iPhone 到底有多少物不符所值。调查了一下,遗憾!AnTuTu 没有 iPhone 版,可能怕对果粉心理打击太大吧。我发现一个有趣的现象,果粉谈到 AnTuTu,不是说没听说(是真不知道还是掩耳盗铃?),就是说 iPhone 不需要 AnTuTu。

    iPhone 虽没有不同硬件厂家的横向对比,但纵向对比 iPhone 4, iPhone 5 也可以看看 iPhone 进步了多少。可是果粉们视 iPhone 如同洪水猛兽,归根到底是害怕看到 iPhone 和 Android 手机、iPad 和 Android 平板设备对比后惨不忍睹的分数。因为害怕,所以果粉们说分数有意思吗?————看优劣得看流畅性、整合度。流畅性和整合度没有客观指标,于是各种争论可以变成了浑水。我想提请果粉注意的是,Android 设备来自众多厂商,硬件参差不齐,我在一台价值 £40 的 Storage Options Scroll 平板上跑一个写汉字软件,确实不流畅,可这个软件跑在 Samsung S3 手机上就非常流畅。如果真要对比流畅性和整合度,就对比一下时下同等价格的 iPhone 和 Android 手机对比,果粉们有这个自信吗?

  • Is Google spreadsheet secure?

    Ctrl+Drag in Google Spreadsheet
    Ctrl+Drag in Google Spreadsheet

    今天我在 Google spreadsheet 操作时发生一件奇怪的事情,让我对 Google spreadsheet 的安全性产生了怀疑。

    我选中了最后一行的两个单元格,“70”和“否”两格,按住了 Ctrl 键,鼠标指向右下角,然后向下拖曳了三格,原想是复制三行“70”和“否”两格。结果出现了如图所示的结果。重试了几次,仍是这样的结果。非常奇怪!是不是复制了别人某个单元格里的内容?

    后来我发现,要复制“70”和“否”两格,不用按住 Ctrl 键,直接拖曳就好了。

    按住了 Ctrl 键,出现的文字是从哪里来的?谁能告诉我?

  • G+ page is a person

    Do you know G+ page is a “person”?

    I mean, as you have a Google account, and fill in G+ profile, you are a G+ person. You start building your cycles, adding people you know (or even don’t know), and posting to individuals, cycles, or Public.

    You can also create one or more G+ pages. What is G+ page? It has confused me for long. Now I know, it is a kind of G+ person, same as you. It was the terminology “Follow” confused me.

    I only find “Follow” on G+ pages. However, “Follow” basically is adding this G+ page to your cycle(s), same as adding some real person. G+ page can also add you to its cycle(s), or not to add you, same as a real person makes such a choice. Even G+ page does not add you, you can still see all its Public posts in your cycle stream, seem as you add President but President does not add you.

    A real person can add another real person or a G+ page to his cycle(s). A G+ page can also add another G+ page or a real person to its cycle(s). This conforms to G+ page is a person.

    Since a real person can create as many G+ pages as he like, and G+ pages can add each other, which make things worse. I mean, a messy social network sharing loads of rubbish.

    Nevertheless, I can not change the world. A network full of rubbish is not something I should worry too much about. What I can do is not to produce rubbish.

    I hope this post is not regarded as a kind of rubbish.

  • Find and share in Google Drive

    我今天才意识到,Google 域用户 Google Drive 共享设置里的 People at some domain find and view / find and edit,指的是用 link 去 find。我一直误以为是可以按 keyword 去 find,或许它会自动出现在域内所有用户的 Shared with me 列表里。

    Google drive share setting
    Google drive share setting

    如果做域内用户共享,应该手动发送 link 给他们;任何一个用户访问过该 link 以后,他的账号会出现在 Who has access 列表里。

    如果手动添加用户账号在 Who has access 里,他才能在 Shared with me 里看到该共享资源。这大概是 Shared with me 之所以叫 Shared with me 而不叫 Shared with us 的原因吧。

  • Social login plugin for WordPress, which one is the best?

    My client is asking a way to manage 3 WordPress sites in one place. I could use WordPress multisite feature by creating a network of sites. However, I felt difficult to control those sites when WordPress multisite was turned on. I would rather have those sites installed into separate databases but have a SSO feature. It is actually what my client is asking for.

    I started looking for a social login plugin for WordPress. I shortlisted four plugins.

    Social login plugins for WordPress
    Social login plugins for WordPress
    • Social Login
    • Social Login for wordpress (LoginRadius)
    • Social Login & Social Sharing by Janrain (Janrain Engage)
    • WordPress Social Login (WP Social Login)

    All installation, I found the first three plugins require create an account with a federal login service provider site of the author, I assume. Although a basic account accommodate 2,500 users or less is free, I do not want to create such an account. It adds risk – everyone can not login if the federal login service provider server is down. Meanwhile, social login is to eliminate create more and more account. I do not want to achieve this goal by creating an intermediate account myself.

    Luckily, I have the forth plugin – WordPress Social Login. It asks me to create Application ID and Applicate Secret with each login service provider. That is what I was expecting.

    It is a coincidence that all the first three social login plugins sit themselves in a top level menu in WordPress sidebar. Are they so important? I am not an aggressive person and I do not like aggressive software.

    WP Social Login modestly sit under Setting menu. That is the way I like!