相关疑难解决方法(0)

从man页面,

MAP_ANONYMOUS
              The mapping is not backed by any file; its contents are initialized to zero.  The fd and offset arguments are ignored; however, some implementations  require
              fd  to  be  -1  if  MAP_ANONYMOUS  (or  MAP_ANON)  is  specified, and portable applications should ensure this.  The use of MAP_ANONYMOUS in conjunction with
              MAP_SHARED is only supported on Linux since kernel 2.4.

使用目的是MAP_ANONYMOUS什么？任何一个例子都会很好.还要从哪里映射内存？

在man页面上写的The use of MAP_ANONYMOUS in conjunction with MAP_SHARED is only supported on Linux …

代码很简单：

#include <vector>
int main() {
    std::vector<int> v;
}

然后，我在Linux上使用Valgrind构建并运行它：

g++ test.cc && valgrind ./a.out
==8511== Memcheck, a memory error detector
...
==8511== HEAP SUMMARY:
==8511==     in use at exit: 72,704 bytes in 1 blocks
==8511==   total heap usage: 1 allocs, 0 frees, 72,704 bytes allocated
==8511==
==8511== LEAK SUMMARY:
==8511==    definitely lost: 0 bytes in 0 blocks
==8511==    indirectly lost: 0 bytes in 0 blocks
==8511==      possibly lost: 0 bytes in 0 blocks
==8511==    still reachable: 72,704 bytes in …