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xconvers

NAME

xconvers - GTK+ convers client for Amateur Radio

DESCRIPTION

Xconvers is a 'split screen' convers client for X. After a connection has been made, the top section of the main window will display the server response, you can type your text in a one-line transmit entry.

Incoming messages are colorized for every user when logged into a convers server.

TIPS

Xconvers uses SO_KEEPALIVE on the connected port. The SO_KEEPALIVE option causes a packet (called a 'keepalive probe') to be sent to the remote system if a long time (2 hours by default) passes with no other data being sent or received. This packet is designed to provoke an ACK response from the peer. This enables detection of a peer which has become unreachable (e.g. powered off or disconnected from the net).

This keepalive time can be changed at runtime from the /proc filesystem. You might be interested in setting this time much shorter, for example when using xconvers over AX.25 with an unstable network:

echo "900" > /proc/sys/net/ipv4/tcp_keepalive_time

will send an ACK packet every 15 minutes.

When using xconvers behind a masquerading firewall, you might encounter timeouts. The server you are connected to will reset the connection if you type something after being idle for more than 15 minutes. The solution for this is changing the timeout value for your masqueraded TCP connection:

ipchains -M -S 14400 0 0

The number 14400 has set the TCP timeout to 4 hours. When typing 'ipchains -M -L', you will see an expire timer which counts down to zero.

SEE ALSO

The xconvers homepage at
http://www.qsl.net/pg4i/linux/xconvers.html

AUTHOR

Both xconvers and this manual page were written by Joop Stakenborg <pg4i@amsat.org>.