Messages in this thread | | | Date | Thu, 27 Mar 2008 17:38:23 +0300 | From | Evgeniy Polyakov <> | Subject | Re: Userspace - Kernel Space "Connector" test |
| |
Hi.
On Wed, Mar 26, 2008 at 03:41:16PM +0530, Midhun A (midhunagni@gmail.com) wrote: > I want to use the Connector module (CONFIG_CONNECTOR) for Kernel > space to User space communication. My kernel version is 2.6.22. > Before using it, I am trying out the example programs in the > Documentation folder. I have cn_test.c built into the kernel (not > loaded as a module) and I have compiled ucon.c.
You have to use smaller index than 32 or increase CN_NETLINK_USERS parameter in include/linux/connector.h
Currently all kernel users fit that limitation, which is ok.
Also, parameter used in bind() is a bitmap of requested groups, to listen on 0x123 idx you have to add it via setsockopt(), which is commented in ucon.c.
So, either switch to smaller group number (connector index) or increase above limit. If you will select the former case (it is simpler from userspace point of view), you have to change bind() group, note that it is a bitmap, os group N equals to (1<<N) bind() value. If you will select the latter case and recompile connector module, then you have to uncomment setsockopt() code in ucon.c
Both methods work, and you will get something like this: $ sudo ./ucon Thu Mar 27 17:29:19 2008 : [123.457] [00000002.00000000]. Thu Mar 27 17:29:20 2008 : [123.457] [00000003.00000000]. Thu Mar 27 17:29:21 2008 : [123.457] [00000004.00000000]. Thu Mar 27 17:29:22 2008 : [123.457] [00000005.00000000]. Thu Mar 27 17:29:23 2008 : [123.457] [00000006.00000000].
-- Evgeniy Polyakov
| |