Tcl UDP

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Overview
Comment:Updated the man doc.
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 05a7d13c00064f8fb90dfb10145636e223fea2f1
User & Date: huubeikens 2014-02-14 07:26:57
Context
2014-02-14
07:35
Updated the changelog. check-in: 60bd166dc5 user: huubeikens tags: trunk
07:26
Updated the man doc. check-in: 05a7d13c00 user: huubeikens tags: trunk
2014-02-13
20:49
The following changes were made: - added IPV6 support - enhanced reuse option for use on all platforms - refactored get/set option functions - enhanced mcastadd/drop option to be able to specify network interface All changes were tested on Windows XP, Linux and macosx (maverick). Units tests were extended. Documentation was updated. check-in: 220bbfdfff user: huubeikens tags: trunk
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Microsoft Platform SDK 2003 is required for building. The following minimal
example will install the extension in the C:\Tcl\lib directory.

	$ cd tcludp/win
	$ nmake -f makefile.vc realclean all 
	$ nmake -f makefile.vc install INSTALLDIR=C:\Tcl\lib










FEEDBACK
========

If you have any problem with this extension, please contact Xiaotao Wu

Name  : Xiaotao Wu
Email : [email protected], [email protected]
URL   : http://www.cs.columbia.edu/~xiaotaow
Phone : (212)939-7020, (212)939-7133,  Fax: (801)751-0217
SIP   : sip:[email protected]






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Microsoft Platform SDK 2003 is required for building. The following minimal
example will install the extension in the C:\Tcl\lib directory.

	$ cd tcludp/win
	$ nmake -f makefile.vc realclean all 
	$ nmake -f makefile.vc install INSTALLDIR=C:\Tcl\lib

DOCUMENTATION BUILD
===================

Use the following command to create the UNIX documentation (based on udp.man file):

	$ cd tcludp
	$ ./tools/mpexpand.tcl nroff ./doc/udp.man ./doc/udp.n
	$ nroff -man ./doc/udp.n

FEEDBACK
========

If you have any problem with this extension, please contact Xiaotao Wu

Name  : Xiaotao Wu
Email : [email protected], [email protected]
URL   : http://www.cs.columbia.edu/~xiaotaow
Phone : (212)939-7020, (212)939-7133,  Fax: (801)751-0217
SIP   : sip:[email protected]

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'\"
'\" Generated from file 'udp.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 1999-2000 Columbia University; all rights reserved
'\"
'\" -*- tcl -*- doctools manpage
'\" To convert this to another documentation format use the mpexpand
'\"           script from tcllib: dtplite -o udp.n nroff udp.man
'\"                               dtplite -o udp.html html udp.man





'\"
.so man.macros


































































































































































































































.TH "udp" n 1.0.9 udp "Tcl UDP extension"
.BS
.SH NAME
udp \- Create UDP sockets in Tcl
.SH SYNOPSIS
package require \fBTcl  8.2\fR
.sp
package require \fBudp  1.0\fR
.sp
\fBudp_open\fR ?\fIport\fR? ?\fIkeywordlist\fR?
.sp
\fBudp_conf\fR \fIsock\fR \fIhost\fR \fIport\fR
.sp
\fBudp_conf\fR \fIsock\fR \fI?-myport?\fR \fI?-remote?\fR \fI?-peer?\fR \fI?-broadcast bool?\fR \fI?-ttl count?\fR
.sp
\fBudp_peek\fR \fIsock\fR ?\fIbuffersize\fR?
.sp
.BE
.SH DESCRIPTION
This package provides support for using UDP through Tcl. The package provides
a new channel type and attempts to permit the use of packet oriented UDP
over stream oriented Tcl channels. The package defined three commands but
\fBudp_conf\fR should be considered depreciated in favour of the standard
Tcl command \fBfconfigure\fR.
.SH COMMANDS
.TP
\fBudp_open\fR ?\fIport\fR? ?\fIkeywordlist\fR?
\fBudp_open\fR will open a UDP socket. If \fIport\fR is specified the UDP
socket will be opened on that port. Otherwise the system will choose a port
and the user can use the \fBudp_conf\fR command to obtain the port number
if required.
.sp
From version 1.0.9 a second argument may be provided. The only valid value is
\'reuse' although others may be added in the future. The reuse keyword sets the
SO_REUSEADDR socket option and permits multiple sockets to be bound to the same

address/port combination.
.TP
\fBudp_conf\fR \fIsock\fR \fIhost\fR \fIport\fR
\fIDeprecated\fR in favour of the standard Tcl \fBfconfigure\fR command.
.sp
\fBudp_conf\fR in this configuration is used to specify the remote destination
for packets written to this \fIsock\fR. You must call this command before
writing data to the UDP socket.
.TP
\fBudp_conf\fR \fIsock\fR \fI?-myport?\fR \fI?-remote?\fR \fI?-peer?\fR \fI?-broadcast bool?\fR \fI?-ttl count?\fR
\fIDeprecated\fR in favour of the standard Tcl \fBfconfigure\fR command.
.sp
In addition to being used to configure the remote host, the \fBudp_conf\fR
command is used to obtain information about the UDP socket. NOTE all these options
are now available using the standard Tcl \fBfconfigure\fR command.
.RS
.TP
................................................................................
Returns the remote hostname and port number for the packet most recently
received by this socket.
.TP
\fI-broadcast ?boolean?\fR
UDP packets can listen and send on the broadcast address. For some systems
a flag must be set on the socket to use broadcast.
With no argument this option will return the broadcast setting. With a
boolean argument the setting can be modified.

.TP
\fI-ttl ?count?\fR
The time-to-live is given as the number of router hops the packet may do. For
multicast packets this is important in specifying the distribution of the
packet. The system default for multicast is 1 which restricts the packet
to the local subnet. To permit packets to pass routers, you must increase the
ttl. A value of 31 should keep it within a site, while 255 is global.
.TP
\fI-mcastadd\fR groupaddr
.TP


\fI-mcastdrop\fR groupaddr
.TP


\fI-mcastgroups\fR
\fBtcludp\fR sockets can support IPv4 multicast operations. To receive
multicast packets the application has to notify the operating system that
it should join a particular multicast group. These are specified as addresses
in the range 224.0.0.0 to 239.255.255.255.






.sp
To view the current set of multicast groups for a channel use \fI-mcastgroups\fR
.TP
\fI-mcastloop ?boolean?\fR
With multicast udp the system can choose to receive packets that it has sent
or it can drop them. This is known as multicast loopback and can be controlled
using this option. By default the value is true and your application will receive
its own transmissions.
.RE
.TP
\fBudp_peek\fR \fIsock\fR ?\fIbuffersize\fR?
Examine a packet without removing it from the buffer.


This function is not available on windows.

.SH EXAMPLES
.PP
.nf

# Send data to a remote UDP socket
proc udp_puts {host port} {
    set s [udp_open]
................................................................................
package. (http://www.neosoft.com/tcl/ftparchive/sorted/comm/tcludp-1.0/)
Compared with Michael's UDP extension, this extension provides Windows
support and provides the ability of using 'gets/puts' to read/write
the socket. In addition, it provides more configuration ability.
.PP
Enhancements to support binary data and to setup the package for the Tcl
Extension Architecture by Pat Thoyts.


.SH "SEE ALSO"
socket(n)
.SH KEYWORDS
networking, socket, udp
.SH COPYRIGHT
.nf
Copyright (c) 1999-2000 Columbia University; all rights reserved

.fi
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'\"
'\" Generated from file './doc/udp.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 1999-2000 Columbia University; all rights reserved
'\"
'\" The definitions below are for supplemental macros used in Tcl/Tk
'\" manual entries.
'\"
'\" .AP type name in/out ?indent?
'\"	Start paragraph describing an argument to a library procedure.
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'\"	the option's class in the option database.
'\"
'\" .UL arg1 arg2
'\"	Print arg1 underlined, then print arg2 normally.
'\"
'\" RCS: @(#) $Id: udp.n,v 1.7 2014/02/14 07:26:57 huubeikens Exp $
'\"
'\"	# Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
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..
.TH "udp" n 1.0.10  "Tcl UDP extension"
.BS
.SH NAME
udp \- Create UDP sockets in Tcl
.SH SYNOPSIS
package require \fBTcl  8.2\fR
.sp
package require \fBudp  1.0\fR
.sp
\fBudp_open\fR ?\fIport\fR? ?\fIreuse\fR? ?\fIipv6\fR?
.sp
\fBudp_conf\fR \fIsock\fR \fIhost\fR \fIport\fR
.sp
\fBudp_conf\fR \fIsock\fR \fI?-myport?\fR \fI?-remote?\fR \fI?-peer?\fR \fI?-broadcast bool?\fR \fI?-ttl count?\fR \fI?-mcastadd "groupaddr ?netwif?"?\fR \fI?-mcastdrop "groupaddr ?netwif?"?\fR \fI?-mcastgroups?\fR \fI?-mcastloop bool?\fR
.sp
\fBudp_peek\fR \fIsock\fR ?\fIbuffersize\fR?
.sp
.BE
.SH DESCRIPTION
This package provides support for using UDP through Tcl. The package provides
a new channel type and attempts to permit the use of packet oriented UDP
over stream oriented Tcl channels. The package defined three commands but
\fBudp_conf\fR should be considered depreciated in favour of the standard
Tcl command \fBfconfigure\fR.
.SH COMMANDS
.TP
\fBudp_open\fR ?\fIport\fR? ?\fIreuse\fR? ?\fIipv6\fR?
\fBudp_open\fR will open a UDP socket. If \fIport\fR is specified the UDP
socket will be opened on that port. Otherwise the system will choose a port
and the user can use the \fBudp_conf\fR command to obtain the port number
if required.
.sp
Additional argument may be provided. If \fIreuse\fR is specified the

SO_REUSEADDR socket option is set which permits multiple sockets to
be bound to the same address/port combination. By default a IPv4 socket is created. When \fIipv6\fR is specified an IPv6
socket is created.
.TP
\fBudp_conf\fR \fIsock\fR \fIhost\fR \fIport\fR
\fIDeprecated\fR in favour of the standard Tcl \fBfconfigure\fR command.
.sp
\fBudp_conf\fR in this configuration is used to specify the remote destination
for packets written to this \fIsock\fR. You must call this command before
writing data to the UDP socket.
.TP
\fBudp_conf\fR \fIsock\fR \fI?-myport?\fR \fI?-remote?\fR \fI?-peer?\fR \fI?-broadcast bool?\fR \fI?-ttl count?\fR \fI?-mcastadd "groupaddr ?netwif?"?\fR \fI?-mcastdrop "groupaddr ?netwif?"?\fR \fI?-mcastgroups?\fR \fI?-mcastloop bool?\fR
\fIDeprecated\fR in favour of the standard Tcl \fBfconfigure\fR command.
.sp
In addition to being used to configure the remote host, the \fBudp_conf\fR
command is used to obtain information about the UDP socket. NOTE all these options
are now available using the standard Tcl \fBfconfigure\fR command.
.RS
.TP
................................................................................
Returns the remote hostname and port number for the packet most recently
received by this socket.
.TP
\fI-broadcast ?boolean?\fR
UDP packets can listen and send on the broadcast address. For some systems
a flag must be set on the socket to use broadcast.
With no argument this option will return the broadcast setting. With a
boolean argument the setting can be modified. This option is not permitted when
using IPv6.
.TP
\fI-ttl ?count?\fR
The time-to-live is given as the number of router hops the packet may do. For
multicast packets this is important in specifying the distribution of the
packet. The system default for multicast is 1 which restricts the packet
to the local subnet. To permit packets to pass routers, you must increase the
ttl. A value of 31 should keep it within a site, while 255 is global.
.TP
\fI-mcastadd\fR groupaddr
.TP
\fI-mcastadd\fR "groupaddr netwif"
.TP
\fI-mcastdrop\fR groupaddr
.TP
\fI-mcastdrop\fR "groupaddr netwif"
.TP
\fI-mcastgroups\fR
\fBtcludp\fR sockets can support IPv4 and IPv6 multicast operations. To receive
multicast packets the application has to notify the operating system that
it should join a particular multicast group. For IPv4 these are specified as addresses
in the range 224.0.0.0 to 239.255.255.255.
.sp
When specifying only the \fIgroupaddr\fR the system will determine the network interface to use.
Specifying the \fInetwif\fR will join a multicast group on a specific network interface.
This is useful on a multihomed system with multiple network interfaces.
On windows you must specify the network interface index. For other platforms the network
interface (e.g. 'eth0') name can be specified.
.sp
To view the current set of multicast groups for a channel use \fI-mcastgroups\fR
.TP
\fI-mcastloop ?boolean?\fR
With multicast udp the system can choose to receive packets that it has sent
or it can drop them. This is known as multicast loopback and can be controlled
using this option. By default the value is true and your application will receive
its own transmissions.
.RE
.TP
\fBudp_peek\fR \fIsock\fR ?\fIbuffersize\fR?
Examine a packet without removing it from the buffer. Option \fIbuffersize\fR specifies the
maximum buffer size. Value must be between 0 and 16.
.sp
This function is not available on windows.
.PP
.SH EXAMPLES
.PP
.nf

# Send data to a remote UDP socket
proc udp_puts {host port} {
    set s [udp_open]
................................................................................
package. (http://www.neosoft.com/tcl/ftparchive/sorted/comm/tcludp-1.0/)
Compared with Michael's UDP extension, this extension provides Windows
support and provides the ability of using 'gets/puts' to read/write
the socket. In addition, it provides more configuration ability.
.PP
Enhancements to support binary data and to setup the package for the Tcl
Extension Architecture by Pat Thoyts.
.PP
Support for IPv6 and allowing a multicast join on a specific network interface is added by Huub Eikens.
.SH "SEE ALSO"
socket(n)
.SH KEYWORDS
networking, socket, udp
.SH COPYRIGHT
.nf
Copyright (c) 1999-2000 Columbia University; all rights reserved

.fi