Hi Don, Correction. The sock already contains the correct proto_ops to use. You have to decided beforehand which is the sock you want to use. Some protocols uses int protocol and may include process id to match the correct sock. Cheers, Jonathan -----Original Message----- From: owner-kernelnewbies@nl.linux.org [mailto:owner-kernelnewbies@nl.linux.org] On Behalf Of Jonathan Khoo Sent: Thursday, October 04, 2001 9:49 AM To: 'Lee Hock Nang, Don'; kernelnewbies@nl.linux.org Subject: RE: kernel socket programming Hi Don, I recommend Steven's book on TCP/IP Illustrated Vol 2. It is mostly on BSD, but it gives you an idea on some of the structures you may find in Linux as well. msghdr and iovec are some examples of similar structures for Linux and BSD. Anyway, /usr/src/linux/net/socket.c contains the portion for sock_sendmsg and sock_recvmsg. Basically, when you call sock_sendmsg, it calls sock->ops->sendmsg. For sock_recvmsg, it's sock->ops->recvmsg. sock is struct sock and ops is struct proto_ops. Depending on what sock you passed into sock_sendmsg, it searches the correct proto_ops to use. iovec contains a pointer to iov_base. You may define your own messaging buffer and pass it into msghdr. Cheers, Jonathan -----Original Message----- From: owner-kernelnewbies@nl.linux.org [mailto:owner-kernelnewbies@nl.linux.org] On Behalf Of Lee Hock Nang, Don Sent: Thursday, October 04, 2001 9:47 AM To: kernelnewbies@nl.linux.org Subject: kernel socket programming Hi, I'm new to kernel space socket programming. Searched the web for some pointers, and only found an article from Linux Magazine on ktftpd. The source code for ktftpd is no longer available in the ftp server as stated in the article. Does anyone have the source code? I wonder is there any sites that I can find more info on kernel space socket programming. I am currently having problem understanding the sock_sendmsg() and sock_recvmsg(). And the struct mshhdr, struct iovec. Also the socket buffer. Many thanks, and have a nice day. Don - Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/ - Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/ - Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/
