sockio —
ioctls that operate directly on sockets
The ioctls listed in this manual page apply directly to
sockets, independent of any underlying protocol. The
setsockopt(3SOCKET) call (see
getsockopt(3SOCKET)) is the primary method for operating on
sockets, rather than on the underlying protocol or network interface.
ioctls for a specific network interface or protocol are
documented in the manual page for that interface or protocol.
SIOCSPGRP- The argument is a pointer to an int. Set the
process-group ID that will subsequently receive
SIGIO or SIGURG signals
for the socket referred to by the descriptor passed to
ioctl to the value of that int.
The argument must be either positive (in which case it must be a process
ID) or negative (in which case it must be a process
group).
SIOCGPGRP- The argument is a pointer to an int. Get the value
of that int to the process-group
ID that is receiving
SIGIO or
SIGURG signals for the socket referred to by the
descriptor passed to ioctl.
SIOCCATMARK- The argument is a pointer to an int. Set the value
of that int to 1 if the read
pointer for the socket referred to by the descriptor passed to
ioctl(2) points to a mark in the data stream for an
out-of-band message. Set the value of that int to
0 if the read pointer for the socket referred to by the
descriptor passed to ioctl does not point to a mark in
the data stream for an out-of-band message.