NAME
udp-receiver - receive files broadcast by udp-sender
SYNOPSIS
./udp-receiver [--file
file] [--pipe pipe] [--portbase portbase]
[--interface net-interface] [--log file] [--ttl
time-to-live] [--mcast-rdv-address mcast-rdv-address]
[--nokbd] [--exitWait milliseconds]
DESCRIPTION
"Udp-receiver" is
used to receive files sent by "udp-sender" (for instance a
disk image).
OPTIONS
Basic options
- --file file
- Writes received data to file. If
this parameter is not supplied, received data is written to stdout
instead.
- --pipe command
- Sends data through pipe after
receiving it. This is useful for decompressing the data, or for
filling in unused filesystem blocks that may have been stripped out
by udp-sender. The command gets a direct handle on the
output file or device, and thus may seek inside it, if needed.
"Udpcast" itself also keeps a handle on the file, which is
used for an informational progress display. The command's
stdin is a pipe from udp-receiver. Example: "udp-receiver -p
"gzip -dc""
- --log file
- Logs some stuff into file.
- --nosync
- Do not open target in synchronous mode.
This is the default when writing to a file or a pipe.
- --sync
- Write to target in synchronous mode. This
is the default when writing to a device (character or block)
- --nokbd
- Do not read start signal from keyboard,
and do not display any message telling the user to press any key to
start.
- --start-timeout sec
- receiver aborts at start if it doesn't see
a sender within this many seconds. Furthermore, the sender needs to
start transmission of data within this delay. Once transmission is
started, the timeout no longer applies.
Networking options
- --portbase portbase
- Default ports to use for udpcast. Two
ports are used: portbase and portbase+1 . Thus,
Portbase must be even. Default is 9000. The same
portbase must be specified for both "udp-sender"
and "udp-receiver".
- --interface interface
- Network interface used to send out the
data. Default is "eth0"
- --ttl ttl
- Time to live for connection request packet
(by default connection request is broadcast to the LAN's broadcast address. If ttl is set, the connection
request is multicast instead to 224.0.0.1 with the given
ttl, which should enable udpcast to work between LANs. Not tested
though.
- --mcast-rdv-address address
- Uses a non-standard multicast address for
the control connection (which is used by the sender and receivers
to ``find'' each other). This is not the address that is
used to transfer the data. By default "mcast-rdv-address"
is the Ethernet broadcast address if "ttl" is 1, and
224.0.0.1 otherwise. This setting should not be used
except in very special situations, such as when 224.0.0.1
cannot be used for policy reasons.
- --exit-wait milliseconds
- When transmission is over, receiver will
wait for this time after receiving the final REQACK. This is done in order to guard against loss of
the final ACK. Is 500 milliseconds by
default.
SEE ALSO
udp-sender
AUTHOR
Alain Knaff