Copyright (c) 2000 Alfred Perlstein
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$FreeBSD: head/share/man/man9/accf_data.9 140458 2005-01-18 20:54:50Z ru $
"
.Dd November 15, 2000 .Os .Dt ACCF_DATA 9 .Sh NAME .Nm accf_data .Nd buffer incoming connections until data arrives .Sh SYNOPSIS .Nm options INET .Nm options ACCEPT_FILTER_DATA .Nm kldload accf_data .Sh DESCRIPTION This is a filter to be placed on a socket that will be using .Fn accept to receive incoming connections.
p It prevents the application from receiving the connected descriptor via .Fn accept until data arrives on the connection.
p The .Fa ACCEPT_FILTER_DATA kernel option is also a module that can be enabled at runtime via .Xr kldload 8 if the INET option has been compiled into the kernel. .Sh EXAMPLES Assuming ACCEPT_FILTER_DATA has been included in the kernel config file or the .Nm module has been loaded, this will enable the data accept filter on the socket .Fa sok . d -literal -offset 0i struct accept_filter_arg afa; bzero(&afa, sizeof(afa)); strcpy(afa.af_name, "dataready"); setsockopt(sok, SOL_SOCKET, SO_ACCEPTFILTER, &afa, sizeof(afa)); .Ed .Sh SEE ALSO .Xr setsockopt 2 , .Xr accept_filter 9 , .Xr accf_http 9 .Sh HISTORY The accept filter mechanism and the accf_data filter were introduced in .Fx 4.0 . .Sh AUTHORS This manual page and the filter were written by .An Alfred Perlstein .