---
title: Operating System dependencies
sort_info: 300
---

Each package set can have one or multiple .osdeps files. These files declare
how to install prepackaged dependencies, based on the underlying operating system.

Defining dependencies between source packages and OS packages
-------------------------------------------------------------

These dependencies can be defined in two ways:

 * by adding a <tt>&lt;osdep name="depname" /&gt;</tt> tag in the package's
   [manifest.xml](manifest-xml.html)
 * by calling <tt>pkg.depends_on_os_package("depname")</tt> [in the autobuild
   file](autobuild.html).

In both cases, depname is used as a key to find the OS package definition in the
osdeps files (see below). It does not have to be the actual package name.

OS packages
-----------

The general format of the an OS package definition:

{coderay:: yaml}
name:
    distribution1,distribution2:
        version1,version2: [package_name1, package_name2]
{coderay}

Where 'name' is the name used to declare the dependency (see above),
<tt>distribution*</tt> the name of the distribution and <tt>version*</tt> the
distribution's version, and <tt>package_name*</tt> the name of the package in
the underlying OS.

Since the osdeps file is a YAML file, <tt>[package_name1, package_name2]</tt> can also be written

{coderay:: yaml}
name:
    distribution1,distribution2:
        version1,version2:
            - package_name1
            - package_name2
{coderay}

If only one package needs to be installed, one can use the shortcut

{coderay:: yaml}
name:
    distribution1,distribution2:
        version1,version2: package_name
{coderay}

Finally, if the package name is version-independent, the version can be omitted:


{coderay:: yaml}
name:
    distribution1,distribution2: package_name
{coderay}

Examples:

{coderay:: yaml}
ruby:
    debian,ubuntu:
        9.04,10.04,sid: libruby-dev
boost:
    debian:
        - libboost1.38-dev
        - libboost-program1.38-dev
    ubuntu:
        9.04,10.04: libboost-dev
{coderay}

At the time of this writing, autoproj is able to install packages on
Ubuntu/Debian and Gentoo. Support for other operating systems can be easily
added, so [contact me](http://github.com/doudou) if you want to do so.

RubyGems packages
-----------------

RubyGems packages are OS-independent. In the osdeps files, they can be referred
to by replacing the OS distribution name by 'gem'.

Example:

{coderay:: yaml}
hoe:
    gem:
        hoe
{coderay}

If the OS dep name and the RubyGems name are the same, one can use the shortcut

{coderay:: yaml}
hoe: gem
{coderay}

Note that it is possible to use a mixture of RubyGems and OS packages. For
instance, the following snippet will both install the gnuplot package and the
gnuplot RubyGems whenever an osdep on 'gnuplot' is declared.

{coderay:: yaml}
gnuplot:
    gem: gnuplot
    debian: gnuplot
{coderay}

Ignoring some dependencies
--------------------------
It is possible that, on some operating systems, a given package should simply be
ignored. To do so, simply use the 'ignore' keyword. Example:

{coderay:: yaml}
gnuplot:
    gem: gnuplot
    debian: ignore
    ubuntu: gnuplot
{coderay}