Setwindow - a program to set tcp window size.

setwindow is an application to set the tcp window size on a machine. You can set the sender and receiver windows independently.

Src is /usr/src/setwindow on topsecret and the executable is in /usr/home/bin.

Running setwindow

setwindow can be found in /usr/home/bin/setwindow on FreeBSD machines.

Running setwindow is simple:

setwindow [-S send_window] [-R recv_window] 

This is just an executable to do the following sysctl commands:

sysctl -w net.inet.tcp.sendspace = send_window


sysctl -w net.inet.tcp.recvspace = recv_window

Note: Even though you've set the TCP window size, you might still need to use setsockopt() to set the send (SO_SNDBUF) and receive (SO_RCVBUF) socket buffer sizes.

Also look at Setting socket buffer sizes.

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Author: Mark Parris
Last updated: Oct 15, 1998