
dknet4 - Data transfer over network (IPv4 only)
===============================================

Overview
--------
The program transfers data over a network connection. It is restricted
to IPv4, but it can be compiled and run on older systems too.
If you need IPv6, please use the dknet program.

Usage
-----

dknet4   -s <port>   [-c <clients>]   [-a <address>/<mask>]*   [<file>]
dknet4   -r <host>:<port>   -t   [<file>]

The -s option configures the program to run as sender. It listens for
incoming connection requests on the specified port.
After finishing all connections the contents of the specified file is
sent over the connections. The program can use multiple connections. After
establishing one connection the program listens for further connection
requests until one of the following conditions is true:
- The maximum number of connections specified by the -c option (default: 1)
  is reached or
- One of the clients uses the -t option to start the transfer.
The argument for the -c option is a non-negative value or the text
"unlimited".
The -a option can be used to restrict the clients allowed to connect. Use
either IPv4 addresses or an IPv4 address / netmask pair. The default settings
allow all connections.

The -r option configures the program to run as receiver. The program
connects to the specified sender and writes the received data to the
specified file or to standard output if no filename is specified.
A client can use the -t option to indicate that the last client has
connected and the server can start the transmission.
If the sender waits for an unlimited number of clients (-c unlimited or -c 0
was used) the last client connecting must use the -t option.

The program returns exit code 0 on success, 1 on error.

