0INSTALL

Section: (1) Updated: 2011 Local index Up

NAME

0install --- a decentralised software installation system

SYNOPSIS

Downloading and running:

0install select URI

0install download URI

0install run URI [ARG]...

0install update URI

Other commands:

0install config [NAME [VALUE]]

0install import FEED

0install list PATTERN

0install add-feed FEED

0install remove-feed [INTERFACE] FEED

0install list-feeds URI

DESCRIPTION

Zero Install is a decentralised cross-distribution software installation system. Programs and libraries are identified by URIs, and there is no need for a central repository. Zero Install ensures that packages cannot conflict with each other and that programs can be shared between mutually untrusting users. See the web-site for more information:

http://0install.net/

The simplest case is to ask 0install to run a program, given its URI. For example:

0install run http://rox.sourceforge.net/2005/interfaces/Edit

The first time you do this, details about available versions of the program are downloaded and cached, along with details about any libraries it depends on.

Zero Install will run a solver to select the best version of each component to use. For example, it will select binaries that are compatible with your CPU and operating system, in your preferred language, and marked "stable" (by default).

If $DISPLAY is set, 0install will display a window where you can confirm (or change) the selected versions.

It will then download the corresponding archives for those version and store them in the cache too. Each package unpacks to its own directory.

Finally, 0install will launch the program, setting environment variables to let it locate its libraries.

GLOBAL OPTIONS

The first non-option argument to 0install is the particular sub-command you want to perform; these are described in detail in the next section.

However, there are some options that apply to all operations. These are:

-c, --console: Never use the GUI. Normally, 0launch switches to graphical mode if it needs to download anything from the network (unless DISPLAY is not set).
-h, --help: Show the built-in help text.
-o, --offline: Run in off-line mode, overriding the default setting. This prevents 0install from checking for updates, and from downloading updates even if it knows about them.
-v, --verbose: More verbose output. Use twice for even more verbose output.
--with-store=DIR: Append a directory to the list of implementation caches. Each sub-directory of DIR contains the contents of one version of a program or library.

SUB-COMMANDS

0install select [OPTIONS] URI

Select a version of the program identified by URI, and compatible versions of all of its dependencies. The information about available version is downloaded if it's not yet in the cache.

The URI can be either an HTTP URL, such as `http://site/program.xml', or a local path name like `/path/to/program.xml'.

For HTTP URLs, the remote file is a signed XML document. If the key is not known and trusted, you will be prompted to accept it first. Local feed files are not signed (any signature will be ignored).

You can also specificy a local selections document, as created previously using the --xml option, rather than a feed. In that case, 0install simply uses those versions without running the solver.

After selecting (but not downloading) a set of versions, the selection is displayed in a human-readable format. Use --xml to get machine-readable output.

If a set of versions cannot be selected using the cached information, 0install will check for updates first.

If a set of versions can be selected based on the currently-cached information, but that information is getting stale, 0install will immediately return the current selection and will also start a background process to check for updates. The `freshness' configuration setting controls when cached information is considered to be stale.

Options for select:

--before=VERSION

Select a version earlier than VERSION (i.e. force the use of an old version of the program). You can only restrict the version of the program itself using this option, not the version of any dependencies.

--command=COMMAND

Some programs provide multiple commands. This selects which one you want. Common values are `run' (the default), `test' (used by 0test) and `compile' (used by 0compile). You can also use --command="" if you don't want to run any command (for example, if the package contains data rather than a program).

--message=MESSAGE

If we show a dialog box for the download, display MESSAGE to the user to explain why the download is needed.

--not-before=VERSION

The selected version must not be earlier than VERSION. e.g. if you want to run version 2.0 or later, use --not-before=2.0.

--refresh

Download a fresh copy of all used feeds before selecting. Normally, cached copies will be used if available (checking for updates later, in the background).

--source

Select source code rather than a binary. This is used internally by `0compile'.

--xml

Print the set of chosen implementations as an XML document to stdout. This can be used later with the `download' and `run' sub-commands.

`select' returns an exit status of zero if it selected a set of versions, and a status of 1 if it could not find a consistent set.

0install download [OPTIONS] URI

This behaves similarly to `0install select', except that it also downloads the selected versions if they are not already cached. Unlike `select', it does not print the selected versions by default.

All options for `select' can also be used for `download'. In addition, these options are available:

--show: Print the selected versions in a human-readable format to stdout.

`download' returns an exit status of zero if it selected a suitable set of versions and they are now all downloaded and in the cache. It returns a status of 1 otherwise.

0install run [OPTIONS] URI [ARGS]

This behaves similarly to `0install download', except that it also runs the program after ensuring it is in the cache.

To avoid having to keep typing the full URI, use the 0alias(1) command to create shortcuts to run your programs.

All options for `select' and `download' can also be used for `run'. In addition, these options are available:

-m, --main=MAIN: Run the specified executable instead of the default. If MAIN starts with '/' then the path is relative to the implementation's top-level directory, whereas otherwise it is relative to the directory containing the default MAIN program. For example, if the default MAIN is bin/svn then using --main=svnadmin will run .../bin/svnadmin instead. This option has been largely superseded by the newer --command option.
-w, --wrapper=WRAPPER: Instead of executing the chosen program directly, run WRAPPER PROGRAM ARGS. This is useful for running debuggers and tracing tools on the program (rather than on 0install!). Note that the wrapper is executed in the environment selected by the program; hence, this mechanism cannot be used for sandboxing. See the DEBUGGING section below.

`run' returns an exit status of 1 if the download step failed. Otherwise, the exit status will be the exit status of the program being run.

0install update [OPTIONS] URI

Check for updates to the program and download them if found. This is similar to 0install download --refresh, except that it prints information about whether any changes were found.

The options are the same as for `select'.

0install import FEED

Import a feed from a local file, as if it had been downloaded from the network. This is useful when testing a feed file, to avoid uploading it to a remote server in order to download it again. The file must have a trusted digital signature, as when fetching from the network.

It is also useful when installing a feed from a CD or similar. Note: to create a full bundle, for archiving or distribution on CD, see 0export(1).

0install add-feed FEED

For example, when you check out a developer version of a project, it may contain an XML feed file. To add this version to the list of available versions, use `add-feed' on the XML file. The file is not copied, so you don't need to re-add the feed each time it is updated. You will probably also want to set the `help_with_testing' configuration option to ensure that testing versions are selected by default.

Note that if you just want to run the program, you can invoke 0install on the feed file directly (without using `add-feed'). This will force the it to use that version, but won't affect what happens when you run it using the URI as normal. Use `add-feed' when you want to use the developer version even when using the URI, or if the program is a library (and thus referenced by URI by other programs).

0install remove-feed [INTERFACE] FEED

Un-register a feed, reversing the effect of `add-feed'. If INTERFACE is not given, you will be prompted to choose which INTERFACE to remove it from.

0install list-feeds URI

List all extra feeds added to URI using `add-feed'.

0install list PATTERN

List all known interface (program) URIs. If a search term is given, only URIs containing that string are shown (case insensitive).

0install config [NAME [VALUE]]

View or change configuration settings.

With no arguments, `0install config' displays all configuration settings. With one argument, it displays the current value of the named setting. With two arguments, it sets the setting to the given value.

0install --version

This can be used (without any command) the get version of 0install itself:

DEBUGGING TIPS

To debug 0install itself, use the --verbose and --console options. For example:

$ 0install -vvc run http://myprog

To trace or debug programs run by 0install, use the --wrapper option. For example, to run myprog --help, displaying all calls to open(2):

$ 0install run --wrapper=strace -e open http://myprog --help

If your program is interpreted (e.g. a Python program), and you wish to debug the interpreter running it, you can do it like this:

$ 0install run --wrapper=gdb --args python http://myprog --help

FILES

Configuration files (see freedesktop.org basedir spec):

~/.config/0install.net/injector/global: Global configuration settings.
~/.config/0install.net/injector/trustdb.xml: List of trusted keys.
~/.config/0install.net/injector/feeds: Per-feed information (e.g. time of last check).
~/.config/0install.net/injector/interfaces: Per-interface settings (preferred stability and any extra feeds that have been registered).

Cached data (can be re-downloaded if lost):

~/.cache/0install.net/interfaces: Downloaded cached feed files.
~/.cache/0install.net/implementations: Downloaded cached implementations, indexed by manifest digest.

See the 0store(1) man page for more information.