xmsgctl - control a message
#include <xio/socket.h>
int xmsgctl(char *xmsg, int opt, void *optval);
Manipulate options for the xmsg, such outofband data and so on.
<xio/socket.h> header defines generic CTL options. The options are as follows:
return the cmsg number.
get one control message from xmsg.
set one control message from xmsg.
clone one xmsg.
copy control message to another xmsg.
remove control message to another xmsg.
On success, xmsg pointer is returned. On error, 0 is returned, and errno is set appropriately.
Supplied allocation size is invalid.
Not enough memory to allocate the message.
Dong Fang <yp.fangdong@gmail.com> Martin Sustrik <sustrik@250bpm.com>