Enabling message queue in 2.6.10 kernel

[Chinmaya Mishra]

Hi All,
I am trying for message queue in linux-2.6.10 kernel.
I export sys_msgget(), sys_msgctl(), sys_msgsnd() and sys_msgrcv() in
the kernel with following EXPORT_SYMBOL(sys_msgget) and so on.
Then compile the kernel, boot with the new image.

My code is like this.
#include <linux/module.h>
#include <linux/kernel.h>

#include <linux/types.h>
#include <linux/ipc.h>
#include <linux/msg.h>
#include <linux/syscalls.h>

#include <asm/system.h>

int msqid, ret;
/* this is the thread function that we are executing */
void mymsgSend(void)
{
       struct msgbuf sbuf;
       printk("Start send message \n");
       memset(&sbuf, '\0', sizeof(sbuf));
       if((msqid = sys_msgget((key_t)1234, 0666 | IPC_CREAT )) < 0) {
               printk("Err: sys_msgget \n");
               return ;
       }
       sbuf.mtype = 1;
       //sprintf(sbuf.mtext,"a");
       ret = sys_msgsnd(msqid, &sbuf, sizeof(sbuf), IPC_NOWAIT);
       printk("Send ret = %d \n", ret);
       if (ret < 0) {
               printk("Err: sys_msgsnd \n");
               return ;
       }
       return ;
}

void mymsgRecv(void)
{
       int msqid;
       struct msgbuf rbuf;
       printk("Start recv message  \n");
       memset(&rbuf, '\0', sizeof(rbuf));
       if ((msqid = sys_msgget((key_t)1234, 0666)) < 0) {
               printk("Err: sys_msgget \n");
               return ;
       }
       rbuf.mtype = 1;
       ret = sys_msgrcv(msqid, (struct msgbuf *)&rbuf, sizeof(rbuf), 
rbuf.mtype, IPC_NOWAIT);
       printk("Recv ret = %d \n", ret);
       if (ret < 0) {
               printk("Err: sys_msgrcv \n");
               return ;
       }
       printk("Mesg Recv = %s \n", rbuf.mtext);
       return;
}

/* load the module */
int init_module(void)
{
             mymsgSend();
             msleep(1000);
             mymsgRecv();
       }
       return(0);
}

/* remove the module */
void cleanup_module(void)
{
       printk("Stop Kernel Thread \n");
       sys_msgctl(msqid, IPC_RMID, NULL);
       return;
}


But the out put messages in # dmesg <enter> is like this

Start send message
Send ret = -14
Err: sys_msgsnd
Start recv message
Recv ret = -42
Err: sys_msgrcv
Stop Kernel Thread

Is there any thing I am missing. Please help soon.


With Regards,
Chinmaya.
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