c - What is the size of HANDLE? -

-

for exercise, @ startupinfo structure. can see last 3 elements has type handle.

so want know size handle has. know size of handle?

the windows handle type isn't opaque type. windows defines couple of properties can depend on. main 1 answer your question: of type void *. windows data types entry on msdn:

handle

a handle object.

this type declared in winnt.h follows:

typedef pvoid handle;

later on in table can see pvoid defined void *.

so handle has same size void *. or in other words, it's 32 bits when using 32-bit compiler , 64 bits when using 64-bit compiler. shouldn't need hard code either of these values in code, instead use sizeof(handle).

the other property of windows handle type obscure, , barely documented: kernel handles the bottom 2 bits zero. shouldn't need depend on in code, , can see never want to. mention completeness , emphasize how microsoft has defined handle more internal implementation detail.


Comments

Post a Comment

Popular posts from this blog

javascript - how to protect a flash video from refresh？ -

-
<!doctype html> <html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> <title>flash video refresh</title> </head> <body> <div id="playerzone"><embed height="496" width="580" flashvars="flvid=19742822&amp;createtime=2012-4-19 13:46:33" wmode="opaque" allowscriptaccess="always" allowfullscreen="true" quality="high" bgcolor="#000000" name="player" id="player" src="swf/mine.swf" type="application/x-shockwave-flash"></div> <a onclick="return test();" id="test">click me popup div,and hide scrollbar</a> </body> the code upon： for example,when click a#test button,popup div,it's no problem,but want hide scrollbar while div popup. i used $('html').css('overflow','hidden') in...
Read more

visual studio 2010 - Connect to informix database windows form application -

-
i trying figure out how connect ibm informix database. have been doing research , have found threads 5 years ago examples not working. i have installed latest sdk ibm informix. i have included ibm.data.informix.dll references in project. i have included using ibm.data.informix; i adding button , on click testing conenction. debug error "sql0035n file "c:\users\adam\documents\visual studio 2010\projects\test\test\msg\en_us\db2nmp.xml" cannot opened." this file not exist , dont see anywhere in program files (x86)\ibm informix client sdk directory. my on click code is private void button1_click(object sender, eventargs e) { const string host = "192.168.obfuscated"; const string servicenum = "1525"; //port? const string server = "serverobfuscated"; const string database = "dbobfuscatedy"; const string user = "myusername"; const string password = ...
Read more

android - Associate same looper with different threads -

-
Image
in application, want create multiple threads working on single queue. create queue know need call looper.prepare() . i want other threads create should associated looper created first thread, how can achieve this? use 1 of java thread safe queue class java.util.concurrent package instead of looper achieve goal. it's more common practice. share queue between threads , post task queue entry 1 thread can entry thread. blockingqueue can - in 1 thread call take() , block thread until thread put() entry queue. that's all. producer consumer pattern example blockingqueue or concurrentlinkedqueue about blockingqueue
Read more