在linux环境下,用gedit+gcc方式学习一段时间的c语言,发现自己越来越佩服linux的牛人了。
居然不用IDE也能开发代码。我做不到,所以有回到了windows的怀抱。

mingw是windows版本的gnu c/c++工具集 主要包括编译器gcc,连接器make,调试器gdb
Eclipse是很好用的开发Java的IDE,CDT的全称是C/C++ Development Tools,是使Eclipse能够支持C/C++开发的插件。
本人使用的开发环境如下:
win7+eclipse +MinGW + CDT

本文的目的:
1)使用eclipse、MingW独构建Windows版的c/c++开发环境
2)编译并调通了一个多线程的程序
eclipse、MingW的安装此处不做重点。

1、配置C/C++开发环境
右击我的电脑,点属性->高级->环境变量。然后:
1)在PATH里加入C:\MinGW\bin
2)新建LIBRARY_PATH变量,值设为C:\MinGW\lib,这是标准库的位置。
3)新建C_INCLUDE_PATH变量,值设为C:\MinGW\include。
4)新建CPLUS_INCLUDE_PATH变量,值为C:\MinGW\include\c++\3.4.2;C:\MinGW\include\c++\3.4.2\mingw32;C:\MinGW\include\c++\3.4.2\backward;C:\MinGW\include

2、设置eclipse的环境变量
Eclipse的Project->Properties->C/C++ Build->Environment中去查看对应的PATH变量
主要是看有没有添加一个包含MinGW的bin目录的PATH变量。这个变量在创建工程的时候一般会自动添加。
但如果没有正确设置PATH变量,编译的时候就会报错说不能运行g++或者gcc。

3、设置多线程动态链接库
Project->Properties->C/C++Build->Settings->Tool Settings->GCC C++ Linker->Libraries
添加Libraries (-l): lpthread

4、一个简单的线程池的例子

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <pthread.h>
#include <assert.h>

typedef struct worker
{
void *(*process) (void *arg);
void *arg;
struct worker *next;

} CThread_worker;

typedef struct
{
pthread_mutex_t queue_lock;
pthread_cond_t queue_ready;

CThread_worker *queue_head;

int shutdown;
pthread_t *threadid;
int max_thread_num;
int cur_queue_size;

} CThread_pool;

int pool_add_worker (void *(*process) (void *arg), void *arg);
void *thread_routine (void *arg);

static CThread_pool *pool = NULL;
void
pool_init (int max_thread_num)
{
pool = (CThread_pool *) malloc (sizeof (CThread_pool));

pthread_mutex_init (&(pool->queue_lock), NULL);
pthread_cond_init (&(pool->queue_ready), NULL);

pool->queue_head = NULL;

pool->max_thread_num = max_thread_num;
pool->cur_queue_size = 0;

pool->shutdown = 0;

pool->threadid =
(pthread_t *) malloc (max_thread_num * sizeof (pthread_t));
int i = 0;
for (i = 0; i < max_thread_num; i++)
{
pthread_create (&(pool->threadid[i]), NULL, thread_routine,
NULL);
}
}

int
pool_add_worker (void *(*process) (void *arg), void *arg)
{
CThread_worker *newworker =
(CThread_worker *) malloc (sizeof (CThread_worker));
newworker->process = process;
newworker->arg = arg;
newworker->next = NULL;

pthread_mutex_lock (&(pool->queue_lock));
CThread_worker *member = pool->queue_head;
if (member != NULL)
{
while (member->next != NULL)
member = member->next;
member->next = newworker;
}
else
{
pool->queue_head = newworker;
}

assert (pool->queue_head != NULL);

pool->cur_queue_size++;
pthread_mutex_unlock (&(pool->queue_lock));
pthread_cond_signal (&(pool->queue_ready));
return 0;
}

int
pool_destroy ()
{
if (pool->shutdown)
return -1;
pool->shutdown = 1;

pthread_cond_broadcast (&(pool->queue_ready));

int i;
for (i = 0; i < pool->max_thread_num; i++)
pthread_join (pool->threadid[i], NULL);
free (pool->threadid);

CThread_worker *head = NULL;
while (pool->queue_head != NULL)
{
head = pool->queue_head;
pool->queue_head = pool->queue_head->next;
free (head);
}
pthread_mutex_destroy(&(pool->queue_lock));
pthread_cond_destroy(&(pool->queue_ready));

free (pool);
pool=NULL;
return 0;
}

void * thread_routine (void *arg)
{
printf ("starting thread 0x%x\n", pthread_self ());
while (1)
{
pthread_mutex_lock (&(pool->queue_lock));
while (pool->cur_queue_size == 0 && !pool->shutdown)
{
printf ("thread 0x%x is waiting\n", pthread_self ());
pthread_cond_wait (&(pool->queue_ready), &(pool->queue_lock));
}

if (pool->shutdown)
{
pthread_mutex_unlock (&(pool->queue_lock));
printf ("thread 0x%x will exit\n", pthread_self ());
pthread_exit (NULL);
}

printf ("thread 0x%x is starting to work\n", pthread_self ());

assert (pool->cur_queue_size != 0);
assert (pool->queue_head != NULL);

pool->cur_queue_size--;
CThread_worker *worker = pool->queue_head;
pool->queue_head = worker->next;
pthread_mutex_unlock (&(pool->queue_lock));

(*(worker->process)) (worker->arg);
free (worker);
worker = NULL;
}
pthread_exit (NULL);
}

// 下面是测试代码

void * myprocess (void *arg)
{
printf ("threadid is 0x%x, working on task %d\n", pthread_self (),*(int *) arg);
_sleep (1);
return NULL;
}

int main (int argc, char **argv)
{
pool_init (3);

int *workingnum = (int *) malloc (sizeof (int) * 10);
int i;
for (i = 0; i < 10; i++)
{
workingnum[i] = i;
pool_add_worker (myprocess, &workingnum[i]);
}
_sleep (5);
pool_destroy ();

free (workingnum);
return 0;
}

5、问题及解决方法
1)build project时出现“Error launching builder (make -k all )”
先将C:\MinGW\bin底下的
mingw32-make.exe更名为make.exe,因为在Eclipse使用时它预设会抓系统里make这个文件名而不是mingw32-make.

2)build project时出现“launch failed,binary not found”
报错是因为没有指定编译器。为了让CDT能够采用MinGW进行编译,需要在 Eclipse 中进行设定
方法一:去Window->Preferences->C/C++->New CDT project wizard->Makefile Project下,找到 Binary Parser 取消 Elf Parser 改选 PE Windows Parser。或是其他编译器,看具体情况而定,
当然你也可以指定GNU ELF Parser。
方法二:去projrct -> properties -> c/c++ build -> settings ->Binary Parser下设置一下,比如使用GNU Elf Parser

3)undefined reference to 'pthread_create'
undefined reference to 'pthread_join'
问题原因:
pthread 库不是 Linux 系统默认的库,由于Mingw下没有带,所以在项目中设置多线程动态链接库,也不管用。
ftp://sourceware.org/pub/pthreads-win32/pthreads-w32-2-8-0-release.exe
解开pthreads-w32-2-8-0-release.exe,把Pre- built.2中的libpthreadGC2.a改名为libpthread.a复制到c:\mingw\lib目录,
pthread.h复制到c: \mingw\include目录即可解决

本文欢迎转载,转载请注明作者与出处
作者:流星
出处:http://blog.sina.com.cn/staratsky