.TH socket_fastopen 3
.SH NAME
socket_fastopen \- enable TCP Fast Open on a server-side TCP socket
.SH SYNTAX
.B #include <libowfat/socket.h>

int \fBsocket_fastopen\fP(int \fIs\fR);
.SH DESCRIPTION
socket_fastopen enables TCP Fast Open support on a server-side TCP
socket.  Call this before socket_listen().  If the platform does not
support this functionality, returns -1 and sets errno to ENOPROTOOPT (or
ENOSYS if the platform does not define ENOPROTOOPT).

Normally socket_fastopen returns 0. If anything goes wrong, socket_fastopen
returns -1, setting errno appropriately.

.SH EXAMPLE
  #include <libowfat/socket.h>

  int \fIs\fR;
  char \fIip\fR[4];
  uint16 \fIp\fR;

  \fIs\fR = socket_tcp4b();
  socket_fastopen(s);
  socket_bind4_reuse(s,ip,p);
  socket_listen(16);

.SH "SEE ALSO"
socket_fastopen_connect4(3), socket_fastopen_connect6(3)