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    Subject;( wrapped source-code, try this[Re: pseudo function-call from kernel to a user-process]
    see the attachment
    --
    Marcel Lanz <marcel.lanz@ds9.ch>

    PGP-Key fingerprint = 71 BE AC 43 04 53 F9 2D 4F B7 B1 47 E5 9B 91 72
    -------------- syscall dkmctl -------
    #define DKM_MAP_REQ 1
    #define DKM_CSD_REG 2
    #define DKM_CSD_DEREG 3
    #define DKM_DOSIG 4
    #define DKM_MAP_RESP 5

    pid_t dkm_csd_pid;
    /*spinlock_t dkm_map_lock = SPIN_LOCK_UNLOCKED;*/

    struct semaphore dkm_map_sema = MUTEX;
    dkm_csd_pid = -1;

    asmlinkage int sys_dkmctl(int cmd, void *arg, void *resp)
    {
    char* node_name;
    node_name = (char*) kmalloc(64, GFP_KERNEL);

    switch(cmd) {
    case DKM_MAP_REQ: /*spin_lock_irqsave(&dkm_map_lock, flags);*/
    down(&dkm_map_sema);
    copy_to_user((char*)arg, "filename", 9);
    break;

    case DKM_MAP_RESP: strncpy_from_user(node_name, arg, strlen_user(arg));
    printk("node to name is: %s\n", node_name);
    /*spin_unlock_irq(&dkm_map_lock);*/
    up(&dkm_map_sema);
    break;

    case DKM_CSD_REG: dkm_csd_pid = *(int*)arg;
    break;

    case DKM_CSD_DEREG: dkm_csd_pid = -1;
    break;

    case DKM_DOSIG: if(dkm_csd_pid > 0)
    force_sig(SIGUSR2, find_task_by_pid(dkm_csd_pid));
    break;
    default: break;
    } /* switch */

    printk("csd_pid is: %d, current->pid is: %d\n", dkm_csd_pid, current->pid);
    kfree(node_name);

    return 0;
    }

    ------------------------------
    signal-handler:

    void on_sigusr2(int signal)
    {
    char* node_name;
    char* buff;

    node_name = (char*) malloc(64);
    buff = (char*) malloc(64);

    printf("sigusr2 from kernel reveived\n");
    dkmctl(DKM_MAP_REQ, buff, NULL);
    printf("buff is: %s\n", buff);
    strcpy(node_name, "orinoco");
    dkmctl(DKM_MAP_RESP, node_name);

    free(node_name);
    free(buff);
    }

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