blocks|key|550514|text|在使用Windows+API的Windows上：TlsAlloc()/TlsSetValue()/TlsGetValue()|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|550515|在Windows上使用编译器内部机制:使用_declspec(thread)|550516|在Linux+(其他POSIX？)上：get_thread_area()和相关|550517|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/windows/desktop/ms686801%2528v=vs.85%2529.aspx|1|http://msdn.microsoft.com/en-us/library/6yh4a9k1.aspx|2|http://linux.die.net/man/2/get_thread_area^0|O|A|0|0|L|H|1|0|J|H|2|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@$A|U|B|V|1|W]]|C|$]]|$1|D|3|E|5|6|7|X|8|@]|9|@$A|Y|B|Z|1|10]]|C|$]]|$1|F|3|G|5|6|7|11|8|@]|9|@$A|12|B|13|1|14]]|C|$]]|$1|H|3|-4|5|6|7|15|8|@]|9|@]|C|$]]]|I|$J|$5|K|L|M|C|$N|O]]|P|$5|K|L|M|C|$N|Q]]|R|$5|K|L|M|C|$N|S]]]]

on Windows using Windows API: <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/ms686801%28v=vs.85%29.aspx">TlsAlloc()</a>/TlsSetValue()/TlsGetValue()

on Windows using compiler intrinsic: use <a href="http://msdn.microsoft.com/en-us/library/6yh4a9k1.aspx">_declspec(thread)</a>

on Linux (other POSIX???) : <a href="http://linux.die.net/man/2/get_thread_area">get_thread_area()</a> and related

blocks|key|767243|text|只需在函数中使用static和__thread即可。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|767244|示例：|767245|int+test(void)
{
++++++++static+__thread+a;

++++++++return+a%2B%2B;
}|code-block|syntax|javascript|767246|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Just use static and __thread in your function.

Example:

<pre><code>int test(void)
{
 static __thread a;

 return a++;
}
</code></pre>

blocks|key|767318|text|你可以让你自己的线程特定的本地存储作为每个线程ID的单例。如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|767319|struct+ThreadLocalStorage
{
++++ThreadLocalStorage()
++++{
++++++++//+initialization+here
++++}
++++int+my_static_variable_1;
++++//+more+variables
};

class+StorageManager
{
++++std::map<int,+ThreadLocalStorage+*>+m_storages;

++++~StorageManager()
++++{+++//+storage+cleanup
++++++++std::map<int,+ThreadLocalStorage+*>::iterator+it;
++++++++for(it+=+m_storages.begin();+it+!=+m_storages.end();+%2B%2Bit)
++++++++++++delete+it->second;
++++}

++++ThreadLocalStorage+*+getStorage()
++++{
++++++++int+thread_id+=+GetThreadId();
++++++++if(m_storages.find(thread_id)+==+m_storages.end())
++++++++{
++++++++++++m_storages[thread_id]+=+new+ThreadLocalStorage;
++++++++}

++++++++return+m_storages[thread_id];
++++}

public:
++++static+ThreadLocalStorage+*+threadLocalStorage()
++++{
++++++++static+StorageManager+instance;
++++++++return+instance.getStorage();
++++}
};|code-block|syntax|javascript|767320|GetThreadId()；是一个特定于平台的函数，用于确定调用者的线程id。如下所示：|767321|int+GetThreadId()
{
++++int+id;
#ifdef+linux
++++id+=+(int)gettid();
#else++//+windows
++++id+=+(int)GetCurrentThreadId();
#endif
++++return+id;
}|767322|现在，在一个线程函数中，你可以使用它的本地存储：|767323|void+threadFunction(void*)
{
++StorageManager::threadLocalStorage()->my_static_variable_1+=+5;+//every+thread+will+have
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++//+his+own+instance+of+local+storage.
}|767324|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

You can make your own thread specific local storage as singleton per thread ID. Something like this:

<pre><code>struct ThreadLocalStorage
{
 ThreadLocalStorage()
 {
 // initialization here
 }
 int my_static_variable_1;
 // more variables
};

class StorageManager
{
 std::map&lt;int, ThreadLocalStorage *&gt; m_storages;

 ~StorageManager()
 { // storage cleanup
 std::map&lt;int, ThreadLocalStorage *&gt;::iterator it;
 for(it = m_storages.begin(); it != m_storages.end(); ++it)
 delete it-&gt;second;
 }

 ThreadLocalStorage * getStorage()
 {
 int thread_id = GetThreadId();
 if(m_storages.find(thread_id) == m_storages.end())
 {
 m_storages[thread_id] = new ThreadLocalStorage;
 }

 return m_storages[thread_id];
 }

public:
 static ThreadLocalStorage * threadLocalStorage()
 {
 static StorageManager instance;
 return instance.getStorage();
 }
};
</code></pre>

GetThreadId(); is a platform specific function for determining caller's thread id. Something like this:

<pre><code>int GetThreadId()
{
 int id;
#ifdef linux
 id = (int)gettid();
#else // windows
 id = (int)GetCurrentThreadId();
#endif
 return id;
}
</code></pre>

Now, within a thread function you can use it's local storage:

<pre><code>void threadFunction(void*)
{
 StorageManager::threadLocalStorage()-&gt;my_static_variable_1 = 5; //every thread will have
 // his own instance of local storage.
}
</code></pre>

blocks|key|767456|text|如果您有权访问C%2B%2B11，还可以使用C%2B%2B11线程本地存储添加。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|767457|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

You can also use the C++11 thread local storage additions if you have access to C++11.

How to define local static variables (that keeps its value between function calls) that are not shared among different threads? 

I am looking for an answer both in C and C++

How to define thread-local local static variables?

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如何定义不在不同线程之间共享的局部静态变量(在函数调用之间保持其值)？我正在寻找C语言和C++语言的答案

问如何定义线程局部静态变量？
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