valgrind工具功能很多，可以动态检测程序运行时的问题，其中一项就是检测内存泄漏。
使用方法： valgrind [options] prog-and-args
用例：
问题程序代码: memleak.c
#include <stdio.h>#include <stdlib.h>main(int argc, char **argv){ char *p = malloc(5); char *q = malloc(10); free(p); //free(q); return;}
运行程序: valgrind ./memleak
输出结果:
==17823== Memcheck, a memory error detector==17823== Copyright (C) 2002-2009, and GNU GPL'd, by Julian Seward et al.==17823== Using Valgrind-3.6.0.SVN-Debian and LibVEX; rerun with -h for copyright info==17823== Command: ./memleak==17823== ==17823== ==17823== HEAP SUMMARY:==17823== in use at exit: 10 bytes in 1 blocks==17823== total heap usage: 2 allocs, 1 frees, 15 bytes allocated==17823== ==17823== LEAK SUMMARY:==17823== definitely lost: 10 bytes in 1 blocks==17823== indirectly lost: 0 bytes in 0 blocks==17823== possibly lost: 0 bytes in 0 blocks==17823== still reachable: 0 bytes in 0 blocks==17823== suppressed: 0 bytes in 0 blocks==17823== Rerun with --leak-check=full to see details of leaked memory==17823== ==17823== For counts of detected and suppressed errors, rerun with: -v==17823== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 12 from 7)
红色字体部分显示程序有两次动态内存分配，共15个字节，只free了一次，内存泄漏10个字节
valgrind缺点：
目前好像只适用于GNU/LINUX x86平台
好好扮演自己的角色，做自己该做的事
