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Feedback: use ioctl()

Forum: How System Calls Work on Linux/i86
Re: Question Are there any sytem calls for sending parameters from userlayer to networklayer (Prasanna)
Date: Sun, 12 Jul 1998 20:45:00 GMT
From: Andrew Ordin <ordin@dialup.ptt.ru>

    Linux has a system call that causes execution of a kernel callback function provided by a network device driver,

ioctl( sock_fd, cmd, ifr )

where sock_fd is a socket file descriptor, cmd is passed
as a parameter to the driver's callback, ifr is a pointer to struct ifrequest (you gotta fill in the name of interface,
eg "eth0" ). You may pass a 32bit value with this call - this may be a pointer in the caller process' address space.

    Mail me for a sample code.