= IMG =

== NAME ==

    img - interdomain multicast gateway

== BUILD/INSTALL ==

=== Requirements ===

    - cmake (Version 2.6+)
    - cmake macro 'FindLibHamcast.cmake'
    - boost libraries developers edition
    - HAMcast library and middleware

=== Build ===

    We recommend an 'out-of-source' cmake-build. Create a new folder, e.g.
    'build' within the source directory. Change to new folder (cd build)
    and run:
{{{
        cmake ../
}}}
    if you have not install libhamcast to standard directories, run:
{{{
        cmake -DHAMCAST_INCLUDE_PATH=<path-to-headers> \
              -DHAMCAST_LIBRARY_PATH=<path-to-libhamcast> ../
}}}
    'path-to-headers' is the absolute path where 'hamcast/hamcast.hpp' can
    be found. 'path-to-libhamcast' is the absolute path where 'libhamcast.so'
    can be found. If both are the same, you have to provide only one of them.
    This will initialize build environment, if no errors occure run:
{{{
        make
}}}
    If build was successful you find the binary in 'build' folder.

=== Install ===

    Currently not supported. Just run img from build directory.

== SYNOPSIS ==

{{{
    img [OPTION]...
}}}

== DESCRIPTION ==

    The program forwards multicast data between distinct HAMcast
    interfaces, i.e. multicast domains, based on configured multicast
    groups subscriptions.

== EXIT STATUS ==

    img exits with status 0 (EXIT_SUCCESS) if no errors occure,
    otherwise 1 (EXIT_FAILURE) is returned.

== OPTIONS ==

    -h, --help
            Print this help screen.

    -l, --list
            List all interfaces.

    -f, --file CONFIG
            Set CONFIG file with group list.

    -g, --group GROUP
            Set multicast GROUP URI.

    -u, --upstream IF
            Set upstream interface id IF.

    -d, --downstream IF
            Set downstream interface id IF.

== EXAMPLES ==

    Without CONFIG file:
{{{
            ./img -g ip://239.238.237.236:1234 -d 1 -u 2
}}}
    With CONFIG file:
{{{
            ./img -f img.cfg -d 1 -u 2
}}}

== FILES ==

    Optional CONFIG file (e.g. img.cfg)

== ENVIRONMENT ==

    LD_LIBRARY_PATH must be set if libhamcast is not installed into
    standard directories, e.g. {{{/usr/lib.}}}

== NOTES ==

    It is mandatory to either specify a config file (-f) or
    a group URI (-g) and interface IDs for upstream and downstream.
    
    Format of config file is: interface-ID=Group-URI