misc device question

[Kevin Wilson]

Hi,
Thanks.
> Isn't this supposed to be called /dev/mymisc ?
Well, your are right ! and with  /dev/mymisc it worked!
sorry for the noise.

BTW, it worked also without  implementing the open() method


rgs
K.

On Wed, Dec 19, 2012 at 10:51 AM, Daniel Baluta <daniel.baluta at gmail.com> wrote:
>
>
> On Wed, Dec 19, 2012 at 10:36 AM, Kevin Wilson <wkevils at gmail.com> wrote:
>>
>> Hello,kernelnewbies
>>
>> I am trying to develop a misc driver in 3.7.0 kernel.
>>
>> As a basis I copy and paste this code, *without any change*,
>>
>> http://virtlog.com/2008/03/25/linux-miscdevice-sample/
>>
>> And build it.
>> after insmod I have :
>> [root at n miscDevice]\>ls -al /dev/mymisc
>> crw------- 1 root root 10, 59 Dec 19 10:24 /dev/mymisc
>>
>>
>> However, when trying to open this file I get:
>> open: No such file or directory
>>
>> Any ideas why ?
>
>
> You should implement open. Check this out [1]
>>
>>
>> The program with which I try to open the device is simple, a few lines
>> following here:
>> int main()
>> {
>>   int fd;
>>
>>   fd = open("/dev/mymodule", O_RDONLY);
>
> Isn't this supposed to be called /dev/mymisc ?
>>
>>         if (fd == -1) {
>>                 perror("open");
>>                 exit(1);
>>         }
>>   printf("open succeeded\n");
>>
>> }
>>
>
> thanks,
> Daniel.
>
> [1] http://lxr.linux.no/#linux+v3.7.1/drivers/char/efirtc.c#L282