|| FreeBSD Kernel Developer's Manual
buffer incoming connections until data arrives
| options ACCEPT_FILTER_DATA
This is a filter to be placed on a socket that will be using
() to receive incoming connections.
It prevents the application from receiving the connected descriptor via accept() until data arrives on the connection.
The ACCEPT_FILTER_DATA kernel option is also a module that can be enabled at runtime via kldload(8) if the INET option has been compiled into the kernel.
Assuming ACCEPT_FILTER_DATA has been included in the kernel config file or the
module has been loaded, this will enable the data accept filter on the socket
struct accept_filter_arg afa;
setsockopt(sok, SOL_SOCKET, SO_ACCEPTFILTER, &afa, sizeof(afa));
HISTORY The accept filter mechanism and the accf_data filter were introduced in
AUTHORS This manual page and the filter were written by