do {} while (0)

http://c2.com/cgi/wiki?TrivialDoWhileLoop

Comments

Post a Comment

Popular posts from this blog

在symbian上随心控制红外线（7） ------ 答疑篇

They have to do with the remote control protocols. Signal gap is the delay between each signal that the remote sends. Signal length is how many 0s and 1s are sent for each code. Repeat codes are used by some remotes to indicate that you're holding a button down -- instead of just sending the same key over and over, it sends the key once and then sends a special code that indicates it's being held. Typical remote controls use a 38KHz carrier wave for modulation, and that normally has a 50% duty cycle.
Read more

[FW] Philips RC-MM Protocol

Image
RC-MM was defined by Philips to be a multi-media IR protocol to be used in wireless keyboards, mice and game pads. For these purposes the commands had to be short and have low power requirements. Whether the protocol is actually used for these purposes today is unknown to me. What I do know is that some Nokia digital satellite receivers use the protocol (9800 series). Features 12 bits or 24 bits per message Pulse position coding, sending 2 bits per IR pulse Carrier frequency of 36kHz Message time ranges from 3.5 to 6.5 ms, depending on data content Repetition time 28 ms (36 messages per second) Manufacturer Philips Transmission timing: In this diagram you see the most important transmission times. The message time is the total time of a message, counting form the beginning of the first pulse until the end of the last pulse of the message. This time can be 3.5 to 6.5 ms, depending on the data content and protocol used. The signal free time is the time in which no signal ma...
Read more

listbox中使用svg图片

Image
这些天尽管有源源不断的pr过来，但是还是有时间搞搞listbox。之所以搞这个是因为在NewLc上看到有不少人问类似的问题，而且我觉得在UI开发中Listbox经常用到。计划在一周内抽时间把S60上的所有标准listbox都深入研究一下。 今天在使用CAknSingleGraphicStyleListBox的时候，没有合适的icon用，正好手边有一些svg图片就试了一下，发现可以使用。这下好了svg图片可大可小，不用考虑尺寸问题。 如果用carbid c++ ide的话，可以直接用ide提供的功能编辑和创建mbm/mif文件。如下图所示启动编辑器 目前，我通过makefile文件生成mif文件。首先创建一个makefile文件icon.mk，然后在bld文件中加入 gnumakefile icon.mk 即可。 其实也可以在mmp文件中加入 prj_extensions start extension s60/mifconc option targetfile icon.mif ..... option source .... end 来替代那个makefile文件 SVG图片的使用方法不同于bmp。bmp通过bmpconv工具被整合为一个mbm（multi-bitmap）文件，这是symbian独有的文件格式。而svg通过mifconv工具整合为mif(MSX interchange format)文件,在Mif文件中也可以加入bmp。 由于mif的支持不是symbian提供的，所以用createiconl这样的方法只能加载mbm文件，不能加载mif文件，需要用aknsutils::creategulicon加载。加载后，使用方法跟通常一样。
Read more