freebsd-hackers,您好!

        
i am test shmat under freebsd 4.8 release(without undate),but a piece of simple code 
wont work.
code like this:
#include<stdio.h>
#include<machine/param.h>
#include<sys/types.h>
#include<sys/ipc.h>
#include<sys/shm.h>
#include <unistd.h>

#define SHM_KEY 100
#define SHM_SIZE 1024
int main(int argc,char *argv[])
{
        int shmid;
        void *shmaddr1,*shmaddr2,*shmaddr3;
        if(shmid=shmget(SHM_KEY,SHM_SIZE,IPC_CREAT|0660)==-1)
        {
                perror("shmget");
                exit(-1);
        }

        printf("shmid: %d\n",shmid);
        if(shmaddr1=shmat(shmid,0,0)==-1)
        {
                perror("shmat 1");
                exit(-1);
        }
        printf("shaddr1:0x%.8x\n",shmaddr1);

        if(shmaddr2=shmat(shmid,0,0)==-1)
        {
                perror("shmat 2");
                exit(-1);
        }
        printf("shaddr2:0x%.8x\n",shmaddr2);
        while(1);
        return 0;
}

then i get error like this:

shmid: 0
shmat 1: Invalid argument
then i use ipcs,find that the shmid is not 0,but an integer number.
-bash-2.05b$ ipcs
Message Queues:
T     ID     KEY        MODE       OWNER    GROUP

Shared Memory:
T     ID     KEY        MODE       OWNER    GROUP
m  65536        100 --rw-rw-rw-     airs    wheel

Semaphores:
T     ID     KEY        MODE       OWNER    GROUP



who can help me? who i can't use the shmid at shmat(shmid,0,0) ? 


        致
礼!
                                

        airsupply
[EMAIL PROTECTED]
          2004-02-07


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