进程1

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <sys/shm.h>
#include <pthread.h>
#include <errno.h>

#define DEBUG 1
#define SHARE_KEY 0x1234
#define THREAD_NUM 4

typedef struct{
	pthread_mutex_t lock;
	pthread_cond_t cond;
	char msg[180];
	int num;
}Share_Stuff;

static Share_Stuff* stuff[THREAD_NUM];

void* threadB(void *prm);


int main(int argc,char** argv)
{
	void *share_addr=NULL;
	pthread_t tid[THREAD_NUM];
	int shmid = -1;
	int ret=0;
	int i=0;

#if DEBUG
	printf("______%s______%s______\n",__DATE__,__TIME__);
#endif

////////////////////////////////////////////share menory////////////////////////////////////////////
	shmid = shmget(SHARE_KEY,sizeof(Share_Stuff), 0666|IPC_CREAT);
	if(shmid == -1){
		printf("Create share memory fail! - %s\n",strerror(errno));
	}

	share_addr=(void*)shmat(shmid,(void*)0,0);
	if(share_addr < 0){
		printf("Get share memory address error! - %s\n",strerror(errno));	
	}

////////////////////////////////////////////get the addr////////////////////////////////////////////
#if DEBUG
	printf("share_addr:%x\n",(unsigned int)share_addr);
#endif

	for(;i<THREAD_NUM;i++){
		stuff[i]=(Share_Stuff*)share_addr+i;
		stuff[i]->num=i;
#if DEBUG
		printf("stuff's addr:%x\n",(unsigned int)stuff[i]);
#endif
	}

	i=0;
////////////////////////////////////////////create_thread////////////////////////////////////////////
	pthread_condattr_t cond_attr;
	pthread_condattr_init(&cond_attr);
	pthread_condattr_setpshared(&cond_attr, PTHREAD_PROCESS_SHARED);

	pthread_mutexattr_t mutex_attr;
	pthread_mutexattr_init(&mutex_attr);
	pthread_mutexattr_setpshared(&mutex_attr, PTHREAD_PROCESS_SHARED);
	
	for(;i<THREAD_NUM;i++){
		pthread_cond_init(&stuff[i]->cond, &cond_attr);
		pthread_mutex_init(&stuff[i]->lock, &mutex_attr);
		ret=pthread_create(&tid[i],0,threadB,(void*)stuff[i]);
		if(ret!=0){
			printf("ThreadA%d create error!\n",i);
		}
	}

	pthread_condattr_destroy(&cond_attr);
	pthread_mutexattr_destroy(&mutex_attr);

	i=0;
////////////////////////////////////////////wait_for_done////////////////////////////////////////////
	for(;i<THREAD_NUM;i++){
		ret=pthread_join(tid[i],NULL);
	}

#if DEBUG
	printf("all thread done!\n");
#endif

	return 0;
}


void* threadB(void *prm)
{
	Share_Stuff *stuff;
	
#if DEBUG
	printf("thread's prm:%x\n",(unsigned int)prm);
#endif

	stuff=(Share_Stuff *)prm;
	while(1){
		sleep(1);
		//printf("pthread_cond_wait\n");
		pthread_cond_wait(&stuff->cond,&stuff->lock);
		printf("message:%s",stuff->msg);
/*******************************************************/
		sleep(3);	
		//printf("pthread_mutex_lock\n");
		pthread_mutex_lock(&stuff->lock);
			sprintf(stuff->msg,"threadA--%d\n",stuff->num);
		//	printf("pthread_cond_signal\n");
			pthread_cond_signal(&stuff->cond);
		//printf("pthread_mutex_unlock\n");
		pthread_mutex_unlock(&stuff->lock);
	}
}

进程2

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <sys/shm.h>
#include <pthread.h>
#include <errno.h>

#define DEBUG 1
#define SHARE_KEY 0x1234
#define THREAD_NUM 4

typedef struct{
	pthread_mutex_t lock;
	pthread_cond_t cond;
	char msg[180];
	int num;
}Share_Stuff;

static Share_Stuff* stuff[THREAD_NUM];

void* threadA(void *prm);


int main(int argc,char** argv)
{
	void *share_addr=NULL;
	pthread_t tid[THREAD_NUM];
	int shmid = -1;
	int ret=0;
	int i=0;

#if DEBUG
	printf("______%s______%s______\n",__DATE__,__TIME__);
#endif

////////////////////////////////////////////share menory////////////////////////////////////////////
	shmid = shmget(SHARE_KEY,sizeof(Share_Stuff), 0666