关于 信号量操作函数semop 报 Invalid argument错误的问题

[only_yestoday]

主函数是把信号量 V了两次,然后又P几次，这是没问题的，当信号量得值变成0之后再V操作的话，信号量的值变成-1后程序就阻塞了。可是当我在当我开了几个线程后，然后在线程里面去进行P操作问题就出来了，如标题写的那样，semop函数会报Invalid argument错误，而且线程不会阻塞。大侠们帮帮忙吧，刚接触LINUX
另外还是工作需要。测试程序如下面，并一起给出MAKEFILE

#include <malloc.h>
#include<sys/types.h>
#include<stdio.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<netdb.h>
#include<ctype.h>
#include<string.h>
#include<unistd.h>
#include<stdlib.h>
#include<errno.h>
#include<signal.h>
#include<sys/wait.h>
#include<sys/select.h>
#include<fcntl.h>
#include<sys/ioctl.h>
#include<sys/time.h>
#include<sys/ipc.h>
#include<sys/sem.h>
#include<pthread.h>

union   semun  
{  
	 int   val;                     //   value   for   SETVAL  
	 struct   semid_ds   *buf;      //   buffer   for   IPC_STAT,   IPC_SET   
	 unsigned short   *array;        //   array   for   GETALL,   SETALL   
                                    //   Linux   specific   part  
	 struct   seminfo   *__buf;     //   buffer   for   IPC_INFO     
};

int sid;

int CreateSem(const char *pathname, int subid, int members, int initvar)
{
	 key_t key;
	 int sid,index;
	 union semun semopts;
	 if((key=ftok(pathname, subid))==-1)
	 {
		  perror("ftok erro!");
		  return -1;
	 }
	 
	 if((sid=semget(key, members, IPC_CREAT))==-1)
	 {
		  perror("Fail to create semaphore !");
		  return -1;
	 }
	 semopts.val = initvar;
	 for(index = 0; index < members; index++)
	 {
		  semctl(key, index, SETVAL, semopts);
	 }
	 return sid;
}

int Delete_Sem(int semid)
{
    union semun semopts;
    if(semctl(semid, 0, IPC_RMID, semopts) == -1)
	{
		 perror("Failed to delete semaphore!");
		 return -1;
	}
	return 0;
	
}

int Set_SemValue(int semid, int index, int value)
{
	 union semun semopts;
	 semopts.val=value;
	 if(semctl(semid, index, SETVAL, semopts) == -1)
	 {
		  perror("Failed to set semaphore!");
		  return -1;
	 }
	 return 0;
}

int Sem_P(int semid, int index)
{
	 struct sembuf buf={0, -1, SEM_UNDO};
	 if(index < 0)
	 {
		  perror("index of arry can not be minus value!");
		  return -1;
	 }
	 buf.sem_num = index;
	 if(semop(semid, &buf, 1) == -1)
	 {
		  perror("semop erro!");
		  return -1;
	 }
	 return 0;
}

int Sem_V(int semid, int index)
{
	 struct sembuf buf={0, 1, SEM_UNDO};
	 if(index < 0)
	 {
		  perror("index of arry can not be minus value!");
		  return -1;
	 }
	 buf.sem_num = index;
	 if(semop(semid, &buf, 1) == -1)
	 {
		  perror("semop erro!");
		  return -1;
	 }
	 return 0;
}

void thread1(void *arg)
{
	 while(1)
	 {
		  printf("thread1 runing\n");
		  sleep(1);
		  Sem_P(sid, 0);
		  int ret=semctl(sid, 0, GETVAL, 0 );
		  printf ("thread1 : %d %d\n", sid,ret);
	 }
}

void thread2(void *arg)
{
	 while(1){
		  printf ("thread2 running\n");
		  sleep(1);
		  Sem_P(sid, 0);
		  int ret=semctl(sid, 0, GETVAL, 0 );
		  printf ("thread 2 : %d %d\n", sid,ret);
	 }
}

void thread3(void *arg)
{
	 while(1)
	 {
		  printf ("thread3 running\n");
		  sleep(1);
//		  int ret=semctl(sid, 0, GETVAL, 0 );
//		  printf ("thread3 : %d %d\n", sid,ret);
	 }
}

int main(int argc, char *argv[], char *envp[])
{
	 pthread_t tid;
	 sid=CreateSem(".", 1, 2, 0);
	 Sem_V(sid, 0);
	 int ret=semctl(sid, 0, GETVAL, 0 );
     printf ("%d %d\n", sid,ret);
	 Sem_V(sid, 0);
	 ret=semctl(sid, 0, GETVAL, 0 );
	 printf ("%d %d\n", sid,ret);
	 Sem_P(sid, 0);
	 ret=semctl(sid, 0, GETVAL, 0 );
	 printf ("%d %d\n", sid,ret);
	 Sem_P(sid, 0);
	 ret=semctl(sid, 0, GETVAL, 0 );
	 printf ("%d %d\n", sid,ret);
	 
	 pthread_create(&tid, NULL, (void*)thread1, NULL);
	 pthread_create(&tid, NULL, (void*)thread2, NULL);
	 pthread_create(&tid, NULL, (void*)thread3, NULL);
	 
	
	 Delete_Sem(sid);
	 
	 sleep(30);

     return 1;
}







//提供个make file可直接调试看效果

APPNAME:=test.out
SRC:=$(wildcard *.c)
OBJS:=$(patsubst %.c,%.o,$(SRC))
OPTFLAG:= -g -mtune=generic
LIBS:= -lpthread

all:$(APPNAME)

$(APPNAME):$(OBJS)
	gcc $(OPTFLAG) $^ $(LIBS) -o $@

clean:
	rm -rf *.o *.out *.d

%.d: %.c
	@set -e; rm -f $@; \
	$(CC) -MM $(CPPFLAGS) $< > $@; \


#-include $(SRC:.c=.d)

.PHONY:all
.PHONY:clean

$(filter %.o,$(OBJS)):%.o:%.c
	gcc -c $(OPTFLAG) $< -o $@

[Carl_CCC]

线程的pthread_t tid;不要定义成一个定义成tid1,tid2,tid3
在Delete_Sem(sid);之前加如下三句

pthread_join( tid, NULL );
pthread_join( tid2, NULL );
pthread_join( tid3, NULL );

不然很快执行这句Delete_Sem(sid); 就不行了。

[only_yestoday]

[only_yestoday]

引用 1 楼 Idle_Cloud 的回复:

线程的pthread_t tid;不要定义成一个定义成tid1,tid2,tid3 在Delete_Sem(sid);之前加如下三句 pthread_join( tid, NULL ); pthread_join( tid2, NULL ); pthread_join( tid3, NULL ); 不然很快执行这句Delete_Sem(sid); 就不行了。

啥也别说了，谢谢你