Re: bug about share Memory

[Bob Proulx]

zhangkeqi84 wrote:
>        Using your System() for a project, I find a bug about the share memory.

You have sent your message to the GNU Coreutils mailing list.  The GNU
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But you are talking about an error in a C program which is apparently
a C program that you have written and this is not a general C
programming support forum.  I do not know where to suggest you to look
for more help.  Very sorry.

Bob

>        The share memory in your system working like this: 
>        the A,B process: 
>        A create the share memory using the struct temp:
>        strcut temp
>        {
>               char *p;
>               char ch;
>        };
>         p =  &ch;
>         ch = 'a';
>          
>        the  share memory will be like this:
>        addr          data content
>        ....
>        0x0F00AB00    (p)0x0F00AB04
>        0x0F00AB04    (ch)'a'
>        ....
>        if process B get the same Share memory with shmat(shmid,0,0);
>          
>        like this
> 
>        addr             data content
>        0x0D002400       (p)0x0F00AB04
>        0x0D002404       (ch) 'a'
> 
>        Using the p in process B,  maybe I will get a “segmentation fault”
> 
>        if process B get the same Share memory with 
> shmat(shmid,addr,SHM_REMAP); //addr is the address of share  memory of  A;  
>       sometimes i will get the segmentation fault in the sentence(shmat) and 
> process dump; 
> 
> 
>        It's very nice that if you can solve this problem asap!
> 
> 
>                                                                      YOURS
>                                                                               
>      keqi zhang
>                 
>                                                                               
>         2007 11 13
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