rospack

rospack overview

rospack is the ROS package management tool. rospack is part dpkg, part pkg-config.

The main function of rospack is to crawl through the packages in ROS_ROOT and ROS_PACKAGE_PATH, read and parse the manifest.xml for each package, and assemble a complete dependency tree for all packages.

Using this tree, rospack can answer a number of queries about packages and their dependencies. Common queries include:

rospack is intended to be cross-platform.

See also

Package manifests

Documentation on manifest.xml files, which rospack crawls and extracts information from.

rosbuild

Documentation for the rosbuild system, which makes heavy use of the rospack commands

rosmake

Documentation for the rosmake command, which makes heavy use of the rospack commands

Crawling algorithm

rospack crawls the directory specified by the environment variable ROS_ROOT. It then crawls the colon-separated directories in ROS_PACKAGE_PATH, in the ordered they are listd, determining a directory to be package if it contains a file called manifest.xml.

If such a file is found, the directory containing it is considered to be a ROS package, with the package name equal to the directory name. The crawl does not descend further once a manifest is found (i.e. packages cannot be nested inside one another).

If a manifest.xml file is not found in a given directory, each subdirectory is searched. This subdirectory search is prevented if a file called rospack_nosubdirs is found. The directory itself is still searched for a manifest, but its subdirectories are not crawled.

If multiple packages by the same name exist within the search path, the first one found wins. It is strongly recommended that you keep packages by the same name in separate trees, each having its own element within ROS_PACKAGE_PATH. That way, you can deterministically control the search order by the way that you specify ROS_PACKAGE_PATH. The search order within a given element of ROS_PACKAGE_PATH can be unpredictably affected by the details of how files are laid out on disk.

Efficiency considerations

rospack re-parses the manifest.xml files and rebuilds the dependency tree on each execution. However, it maintains a cache of package directories in ROS_ROOT/.rospack_cache. This cache is updated whenever there is a cache miss, or when the cache is 60 seconds old. You can change this timeout by setting the environment variable ROS_CACHE_TIMEOUT, in seconds. Set it to 0.0 to force a cache rebuild on every invocation of rospack.

rospack’s performance can be adversely affected by the presence of very broad and/or deep directory structures that don’t contain manifest files. If such directories are in rospack’s search path, it can spend a lot of time crawling them only to discover that there are no packages to be found. You can prevent this latency by creating a rospack_nosubdirs file in such directories. If rospack seems to be running annoyingly slowly, you can use the profile command, which will print out the 20 slowest trees to crawl (or use profile --length=N to print the slowest N trees).

rospack_nosubdirs

You can prevent rospack from descending into a directory by simply adding an empty rospack_nosubdirs file. This is useful when you want to block off part of your package tree, either for performance reasons, or to hide another version of your code.

We recommend creating a rospack_nosubdirs file in packages that checkout code from other code repositories, as those often create big directory trees that don’t get cleaned up if a package is moved or deleted.

NOTE: the rospack_nosubdirs directive only affects the rospack tool. It is not observed by tools like roslaunch or rosrun.

rospack usage

The rospack tool implements many commands that print information about ROS packages. All of these commands print their results to stdout. Any errors or warnings go to stderr. This separation ensures that error output does not confuse programs that execute rospack as a subprocess to, for example, recover build flags for a package.

USAGE: rospack <command> [options] [package]
  Allowed commands:
    help [subcommand]
    cflags-only-I     [--deps-only] [package]
    cflags-only-other [--deps-only] [package]
    depends           [package] (alias: deps)
    depends-indent    [package] (alias: deps-indent)
    depends-manifests [package] (alias: deps-manifests)
    depends-msgsrv    [package] (alias: deps-msgsrv)
    depends-on        [package]
    depends-on1       [package]
    depends-why --target=<target> [package] (alias: deps-why)
    depends1          [package] (alias: deps1)
    export [--deps-only] --lang=<lang> --attrib=<attrib> [package]
    find [package]
    langs
    libs-only-L     [--deps-only] [package]
    libs-only-l     [--deps-only] [package]
    libs-only-other [--deps-only] [package]
    list
    list-duplicates
    list-names
    plugins --attrib=<attrib> [--top=<toppkg>] [package]
    profile [--length=<length>] [--zombie-only]
    rosdep  [package] (alias: rosdeps)
    rosdep0 [package] (alias: rosdeps0)
    vcs  [package]
    vcs0 [package]
  Extra options:
    -q     Quiets error reports.

 If [package] is omitted, the current working directory
 is used (if it contains a manifest.xml).

General options

-q

The -q option can be given after any subcommand. It will suppress most error messages that usually go to stderr. The return code will still be non-zero, to indicate the error. E.g., to search for a package, but suppress the error message if it’s not found:

$ rospack find -q foo
$ echo $?
255

NOTE: for all commands, if [package] is omitted, the current working directory is used.

rospack help [subcommand]

Print help message. Since 2.0.9, you can give a subcommand as an argument to get more specific help.

rospack find [package]

Print absolute path to the package, empty string if package is not found. This is used within many tools, including rosbuild.

Example:

$ rospack find roscpp
/Users/homer/code/ros/core/roscpp

rospack list

Print newline-separated list, <package-name> <package-dir>, for all packages.

Example:

$ rospack list | grep visualization
wxpropgrid /home/kwc/ros-pkg/visualization/wxpropgrid
rviz /home/kwc/ros-pkg/visualization/rviz
visualization_msgs /home/kwc/ros-pkg/visualization_common/visualization_msgs
ogre /home/kwc/ros-pkg/visualization_common/ogre
ogre_tools /home/kwc/ros-pkg/visualization_common/ogre_tools

rospack list-names

Print newline-separated list of packages names for all packages.

rospack list-duplicates

Print newline-separated list of names of packages that appear more than once during the search.

rospack langs

Print space-separated list of available language-specific client libraries. The client library list is calculated as the list of packages that depend directly on the placeholder package “roslang”, minus any packages that are listed in the environment variable ROS_LANG_DISABLE.

Example:

$ rospack langs
roscpp rospy

rospack depends [package]

Print newline-separated, ordered list of all dependencies of the package. This is used within rosmake.

Example:

$ rospack depends map_server
gtest
genmsg_cpp
roslib
xmlrpc++
rosthread
roscpp
std_msgs
std_srvs
sdl
ijg_libjpeg
sdl_image

rospack depends1 [package]

Print newline-separated, ordered list of immediate dependencies of the package.

rospack depends-manifests [package]

Print space-separated, ordered list of manifest files for all dependencies of the package. This is used by rosbuild to create explicit dependencies from source files to other packages’ manifests.

rospack depends-indent [package]

Print newline-separated list of the entire dependency chain for the package, indented to indicate where in the chain each dependency arises. This may contain duplicates.

rospack depends-why –target=<target> [package]

Print newline-separated presentation of all dependency chains from the package to <target>.

rospack depends-on [package]

Print newline-separated list of all packages that depend on the package.

rospack depends-on1 [package]

Print newline-separated list of all packages that directly depend on the package.

Example:

$ rospack depends-on1 roslang
roscpp
rospy
rosoct
roslisp

rospack rosdep [package]

Print newline-separated list of all rosdep tags from the manifest.xml of the package and all of its dependencies.

rospack rosdep0 [package]

Print newline-separated list of all rosdep tags from the manifest.xml of just the package itself.

rospack vcs [package]

Print newline-separated list of all versioncontrol tags from the manifest.xml of the package and all of its dependencies. This is useful for pre-caching SSL certificates for https SVN servers that will be contacted during the build, to avoid having to manually accept the certificates during the build.

rospack vcs0 [package]

Print newline-separated list of all versioncontrol tags from the manifest.xml of just the package itself. This is useful for pre-caching SSL certificates for https SVN servers that will be contacted during the build, to avoid having to manually accept the certificates during the build.

rospack export –lang=LANGUAGE –attrib=ATTRIBUTE [package]

Print space-separated list of [export][LANGUAGE ATTRIBUTE=””/][/export] values from the manifest of the package and its dependencies.

This is useful for getting language-specific build flags, e.g,. export/cpp/cflags.

--deps-only

If –deps-only is provided, then the package itself is excluded.

rospack cflag-only-I, cflags-only-other

NOTE: the cflags-only-* commands are simply variants of the rospack export command with additional processing.

cflags-only-I [package]

Print space-separated list of export/cpp/cflags that start with -I. This is used by rosbuild to assemble include paths for compiling.

cflags-only-other [package]

Print space-separated list of export/cpp/cflags that don’t start with -I. This is used by rosbuild to assemble non-include compile flags.

--deps-only

If --deps-only is provided, then the package itself is excluded. This can be used with all cflags-only-* variants.

rospack libs-only-L, libs-only-l, libs-only-other

NOTE: the libs-only-* commands are simply variants of the rospack export command with additional processing.

libs-only-L [package]

Print space-separated list of export/cpp/libs that start with -L. If –deps-only is provided, then the package itself is excluded. This is used by rosbuild to assemble library search paths for linking.

libs-only-l [package]

Print space-separated list of export/cpp/libs that start with -l. If –deps-only is provided, then the package itself is excluded. This is used by rosbuild to assemble libraries for linking.

libs-only-other [package]

Print space-separated list of export/cpp/libs that don’t start with -l or -L. Used by rosbuild to assemble non-library link flags.

--deps-only

If --deps-only is provided, then the package itself is excluded. This can be used with all libs-only-* variants.

rospack profile

--length=N

Force a full crawl of package directories (i.e., don’t use cache, and report to console on the N (default 20) directories that took the longest time to crawl. Useful for finding stray directories that are adversely affecting rospack’s performance.

--zombie-only

Only print directories that do not have any manifests. In this case, the output can be fed directly into rm to clean up your tree, e.g.:

rospack profile --zombie-only | xargs rm -rf

NOTE: be sure to check the output before deleting any files!

rospack plugins –attrib=<attrib> [package]

Examine packages that depend directly on the given package, extracting from each the name of the package followed by the value of an exported attribute with the name <attrib>. All matching exports are returned, newline-separated, e.g., if the manifest for a package “foo,” located at /tmp/foo, contains:

<depend package="rosbuild"/>
<export>
  <rosbuild cmake="${prefix}/cmake/foo.cmake/>
</export>

then rospack plugins --attrib=cmake rosbuild will return (at least):

foo /tmp/foo/cmake/foo.cmake
--top=<toppkg>

If --top is given, then in addition to depending directly on the given package, to be scanned for exports, a package must also be a dependency of <toppkg>, or be <toppkg> itself.