The @dfn{Ham Radio Control Libraries}, @dfn{Hamlib} for short, is a
development effort to provide a consistent interface for programmers
wanting to incorporate radio control in their programs.

Hamlib is not a complete user application, rather, it is a software
layer intended to make controlling various radios and other shack
hardware much easier. Hamlib will allow authors of such software as
logging programs, digital communications programs, or those wanting to
develop the ultimate radio control software to concentrate on the user
interface and the basic function of the program rather than radio
control.  Hamlib consists of several parts, the programming library,
utility programs, and library interfaces to other programming languages.

Most recent amateur radio transceivers allow external control of their
functions through a serial interface. Unfortunately, control commands
are not always consistent across a manufacturer's product line and each
manufacturer's product line differs greatly from its competitors.

Hamlib attempts to solve this problem by presenting a "virtual radio" to
the programmer by providing an interface to actions such as setting a
given VFO's frequency, setting the operating mode, querying the radio of
its current status and settings, and giving the application a list of a
given radio's capabilities. Unfortunately, what can be accomplished by
Hamlib is limited by the radios themselves and some offer very limited
capability.

Other devices, such as antenna rotors, can be placed into the Hamlib
control scheme. Other recent developments include network interface
servers and a USB interface capability. Language bindings are provided
for C, C++, Perl, Python, Lua and TCL (more to come).

@menu
* Overview::
* The Hamlib project::
* Applications using Hamlib::
* Licensing implications::
* Radio cloning::
* Pronunciation::
@end menu

@node Overview
@section A view from the top of the tower
@cindex Overview

@cindex Front end library
@cindex Virtual radio
@cindex Virtual rotor
Hamlib is a @dfn{front end} library providing a @emph{C} language
Application Programming Interface @acronym{API} to programmers wishing
to integrate radio or rotor control in their applications.  Hamlib
presents a @dfn{virtual radio} or @dfn{virtual rotor} that is a
consistent interface to an application despite wide differences in radio
and rotor interfaces and capabilities.

@cindex Back end library
The front end library uses a number of @dfn{back end} libraries to
translate from the front end to the various individual radio and
rotor models.  A back end library handles conversion of the
front end variables to the format needed by the radio or rotor
device it controls.  The back end libraries are generally grouped by
manufacturer and in some cases by a common control protocol.

@quotation
Since a picture is worth quite a few words, here is a visual representation
of Hamlib's design.
@ifhtml
@*@*
@end ifhtml
@float Figure, fig:img1
@image{Hamlib_design,,,Hamlib Design}
@caption{Hamlib design---@i{courtesy of Martin Ewing, AA6E}.}
@shortcaption{Hamlib design}
@end float
@*
@end quotation

@cindex Scripting languages
@cindex Languages, scripting
@cindex Interface, languages
Hamlib also provides an interface library for each of several common
@dfn{scripting} languages such as @url{http://www.perl.org, Perl, Perl},
@url{http://www.python.org, Python, Python}, @url{https://www.lua.org, Lua, Lua}
and @url{http://www.tcl.tk, TCL, TCL}.  These language @dfn{bindings} are
generated through the use of @url{http://www.swig.org, SWIG, SWIG} a parser/generator
for multiple language interfaces to a C library.  A native generated @emph{C++}
language interface is also provided.

@cindex Daemon, network
@cindex Network, daemon
Besides the C and supplemental APIs, Hamlib also provides a pair of
network daemons that provide a text command based API for controlling
an attached radio or rotor through a @emph{TCP/IP} network connection.
The daemons then handle the interface to the Hamlib C API.

More than one type of device, radio or rotor, may be controlled at a
time, however, there is generally a limit of one device per serial port
or other port.

@node The Hamlib project
@section Hamlib project information
@cindex Hamlib project
@cindex Project, Hamlib

The Hamlib Project was founded by Frank Singleton,VK3FCS/KM5WS in July
2000.  Shortly after Stephane Fillod, F8CFE, joined Frank on the Hamlib
project and the API and implementation development led to a reasonable
level of maturity in a few years.  A major milestone was reached when
Hamlib 1.2.0 was released in March 2004.  The API and Application
Binary Interface (@acronym{ABI}) interfaces have remained stable since
that time up to the latest release of 1.2.15.3 in late 2012.

Development continues with a bump of the public version number to 3.0
(essentially simply dropping the ``1.'' of previous releases).  While some
API tweaks are planned, ABI compatibility with the prior 1.2.@i{x}
releases remains a priority.  Other goals include streamlining the
build system (done), improving the SWIG generated language bindings
(in progress), improving the overall documentation (this manual, in
progress), and other updates as warranted.

The Project is hosted by @url{https://sourceforge.net/,
SourceForge.net} at the @url{https://sourceforge.net/projects/hamlib/,
Hamlib project page} and the
@url{http://sourceforge.net/apps/mediawiki/hamlib/index.php, Hamlib
Wiki}.

Development discussion and most user support take place on the
@url{https://sourceforge.net/p/hamlib/mailman/, hamlib-developer mailing
list}.  While there are
@url{https://sourceforge.net/p/hamlib/discussion/, SourceForge.net
discussion forums}, they are rarely used and not as closely read by the
developers as the mailing list.

For @dfn{source code management}, the project uses
@url{http://git-scm.com/, Git}, a fast, distributed content tracker.
Among its features is that every developer has the complete Hamlib
development history available locally.  While a canonical Git
repository is hosted as SourceForge, its availability is not essential to
continued development, although development work flows would change
temporarily.  For more information on using Git, @pxref{Working with
Git}.

@quotation Note
The SourceForge.net Web interface to the Hamlib Git repository is
currently broken (a ticket is pending) as of late February, 2013.  A
mirror exists at @url{https://github.com/N0NB/hamlib, GitHub} which
supports browsing via the Web and other Git commands.  Access of the
SF.net repository by other means (SSH or Git protocols) is unaffected
by this issue.
@end quotation

@node Applications using Hamlib
@section Applications using Hamlib
@cindex Hamlib applications
@cindex Applications, using Hamlib

A number of application developers have taken advantage of Hamlib's
capabilities to implement radio and/or rotor control.  While not
exhaustive, a list is maintained at the Hamlib Wiki,
@url{https://sourceforge.net/apps/mediawiki/hamlib/,
Applications/Screenshots}.  Developers are encouraged to request their
applications be added to the gallery by way of the hamlib-developer
mailing list.

@node Licensing implications
@section Using Hamlib with your program
@cindex Hamlib licensing
@cindex Licensing, Hamlib

As with other Free Software projects, Hamlib relies heavily on copyleft
licensing to encourage development contributions and provide an open
atmosphere for development.  Hamlib's source code is released under two
licenses, the @acronym{LGPL} for the library portion, and the
@acronym{GPL} for the utility programs.

The LGPL allows the library to be used (linked) by programs regardless
of their individual license.  However, any contributions to the library
source remain under copyleft which means that the library source code
may not be used in violation of the terms of the LGPL.

The utility program source files are released under the GPL.  Any direct
use of these sources must be in a form that complies with the terms of
the GPL.  Concepts learned by studying these sources for the purpose of
understanding the Hamlib API is not covered nor prohibited by the GPL,
however, directly copying GPL sources into any work that is incompatible
with the terms of the GPL is prohibited.

@xref{Copying and Redistribution}.

@node Radio cloning
@section Radios with a clone capability
@cindex Radio cloning
@cindex Cloning, radio

Hamlib's focus is on controlling rigs that employ a port and command
protocol for setting frequency, mode, VFO, PTT, etc. Most VHF/UHF
transceivers do not employ such control capability but do provide for
cloning the memory contents from radio to another of the same model. A
related project, @url{http://chirp.danplanet.com/, CHIRP}, aims to
support rigs with such a clone capability. Please contact the CHIRP
project for support of such rigs.

@node Pronunciation
@section Pronouncing Hamlib
@cindex Pronouncing Hamlib
@cindex Hamlib, pronouncing

English speakers seem to have two alternate pronunciations for our
project:

@itemize @bullet
@item Hamlib (Ham - lib, long "i", as in library.) IPA style: /'ham læb/
@item Hamlib (Ham - lib, short "i", as in liberty.) IPA style: /'ham lɪb/
@end itemize

Then again, we have people who say Linux "L-eye-nux" and those who say
"L-in-nux"...

If you're French, the above does not apply! :-)
