hi,
actually i'm using a socket of type SOCK_STREAM. i also set the
MSG_WAITALL flag within the sock_recvmsg but this causes that socket hangs
up. the return code in this case is -512.
i cant find any data about it...
any hints?????
regards
benny
Rithin Kumar Shetty sagte:
> What type of socket are you using ? I mean there are several types of
> them :
> SOCK_STREAM, SOCK_DGRAM, SOCK_RAW etc. Which one did you use ?
> Based on the type of the socket functions like tcp_recvmsg, udp_recvmsg
> etc are called
> from sock_recvmsg when it calls sock->ops->recvmsg(). So you may want
> to look at those
> functions to know what is happening.
>
> Hope this Helps,
> Rithin.
>
>
> TI8 Benjamin Kohler wrote:
>
>>hi,
>>
>>i just wrote a kernel module which sends some data to a server. after
>> the server has received the data it sends back some data to the kernel
>> module. sending data from the module to the server works! but i cant
>> get the response sent by the server.
>>for receiving data within my kernel module i use the sock_recvmsg
>> function. the return value is always 0. does anybody know how i have
>> exactly to use this function so that i can receive any data within my
>> kernel module
>>
>>here is my Send_Msg function within my Kernel Module:
>>
>>
>>int Send_Msg(const char *buffer)
>>{
>> struct msghdr send_msg;
>> struct msghdr recv_msg;
>> struct iovec iov;
>> struct timeval now1;
>> mm_segment_t oldfs;
>> int error,i,len,lat;
>> char recv_buf[1024];
>> int j = 0;
>>
>>
>> iov.iov_base=(void *)buffer;
>> iov.iov_len=strlen(buffer);
>> printk("<1>Size of Buffer in Send_Msg: %d\n", sizeof(buffer));
>>
>> send_msg.msg_name=NULL;
>> send_msg.msg_namelen=0; //sizeof(server);
>> send_msg.msg_iov=&iov;
>> send_msg.msg_iovlen=1;
>> send_msg.msg_control=NULL;
>> send_msg.msg_controllen=0;
>> send_msg.msg_flags = 0;
>>
>> do_gettimeofday(&now1);
>>
>> oldfs = get_fs(); set_fs(KERNEL_DS);
>> error = sock_sendmsg(Socket[0], &send_msg, (size_t)buffer);
>> set_fs(oldfs);
>>
>> iov.iov_base=(void *)recv_buf;
>> iov.iov_len=sizeof(recv_buf);
>>
>> recv_msg.msg_name=NULL;
>> recv_msg.msg_namelen=0; //sizeof(server);
>> recv_msg.msg_iov=&iov;
>> recv_msg.msg_iovlen=1;
>> recv_msg.msg_control=NULL;
>> recv_msg.msg_controllen=0;
>> recv_msg.msg_flags = 0;
>>
>> udelay(1000);
>>
>>
>> oldfs = get_fs(); set_fs(KERNEL_DS);
>> len = sock_recvmsg(Socket[0], &recv_msg, (size_t)recv_buf,
>> MSG_WAITALL); set_fs(oldfs);
>>
>> if (len<0)
>> printk(KERN_ALERT "ERRO receive ########\n");
>>
>> if (error<0)
>> printk(KERN_ALERT "Erro send msg ERRO = %d
>> buffer=%s\n",error,buffer);
>>
>> printk("<1>recieved bytes: %d\n", len);
>>
>>
>> sock_release(Socket[0]);
>> return 0;
>>}
>>
>>
>>the sock_sendmsg works fine, but the sock_recvmsg() always seems to
>> fail!!! Any help out there???
>>
>>
>>greetings
>>benny
>>
>>
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