Fedora Packaging Guidelines for RPM Scriptlets

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RPM spec files have several sections which allow packages to run code on installation and removal. These bits of code are called scriptlets and are mostly used to update the running system with information from the package. This page offers a quick overview of RPM scriptlets and a number of common recipes for scriptlets in packages. For a more complete treatment of scriptlets, please see the Maximum RPM book.

The version of RPM in Fedora also has functionality to automatically run scripts when files are placed in certain locations. (See [1].) This potentially obviates the need for most of the scriptlets on this page, but is not currently implemented in all cases where it could be.

Default Shell

In Fedora, all scriptlets can safely assume they are running under the bash shell unless a different language has been specified.


The basic syntax is similar to the %build, %install, and other sections of the rpm spec file. The scripts support a special flag, -p which allows the scriptlet to invoke a single program directly rather than having to spawn a shell to invoke the programs. (ie: %post -p /sbin/ldconfig)

When scriptlets are called, they will be supplied aith an argument. This argument, accessed via $1 (for shell scripts) is the number of packages of this name which will be left on the system when the action completes, except for %pretrans and %posttrans which are always run with $1 as 0.. So for the common case of install, upgrade, and uninstall we have:

install upgrade uninstall
 %pretrans $1 == 0 $1 == 0 (N/A)
 %pre $1 == 1 $1 == 2 (N/A)
 %post $1 == 1 $1 == 2 (N/A)
 %preun (N/A) $1 == 1 $1 == 0
 %postun (N/A) $1 == 1 $1 == 0
 %posttrans $1 == 0 $1 == 0 (N/A)

Note that these values will vary if there are multiple versions of the same package installed (This mostly occurs with parallel installable packages such as the kernel and multilib packages. However, it can also occur when errors prevent a package upgrade from completing.) So it is a good idea to use this construct:

if [ $1 -gt 1 ] ; then

...for %pre and %post scripts rather than checking that it equals 2.

All scriptlets MUST exit with the zero exit status. Because RPM in its default configuration does not execute shell scriptlets with the -e argument to the shell, excluding explicit exit calls (frowned upon with a non-zero argument!), the exit status of the last command in a scriptlet determines its exit status. Most commands in the snippets in this document have a "|| :" appended to them, which is a generic trick to force the zero exit status for those commands whether they worked or not. Usually the most important bit is to apply this to the last command executed in a scriptlet, or to add a separate command such as plain ":" or "exit 0" as the last one in a scriptlet. Note that depending on the case, other error checking/prevention measures may be more appropriate.

Non-zero exit codes from scriptlets can break installs/upgrades/erases such that no further actions will be taken for that package in a transaction (see #Scriptlet Ordering below), which may for example prevent an old version of a package from being erased on upgrades, leaving behind duplicate rpmdb entries and possibly stale, unowned files on the filesystem. There are some cases where letting the transaction to proceed when some things in scriptlets failed may result in partially broken setup. It is however often limited to that package only whereas letting a transaction to proceed with some packages dropped out on the fly is more likely to result in broader system wide problems.


The scriptlets in %pre and %post are respectively run before and after a package is installed. The scriptlets %preun and %postun are run before and after a package is uninstalled. The scriptlets %pretrans and %posttrans are run at start and end of a transaction. On upgrade, the scripts are run in the following order:

  1.  %pretrans of new package
  2.  %pre of new package
  3. (package install)
  4.  %post of new package
  5.  %triggerin of other packages (set off by installing new package)
  6.  %triggerin of new package (if any are true)
  7.  %triggerun of old package (if it's set off by uninstalling the old package)
  8.  %triggerun of other packages (set off by uninstalling old package)
  9.  %preun of old package
  10. (removal of old package)
  11.  %postun of old package
  12.  %triggerpostun of old package (if it's set off by uninstalling the old package)
  13.  %triggerpostun of other packages (if they're setu off by uninstalling the old package)
  14.  %posttrans of new package

The %pretrans Scriptlet

Note that the %pretrans scriptlet will, in the particular case of system installation, run before anything at all has been installed. This implies that it cannot have any dependencies at all. For this reason, %pretrans is best avoided, but if used it MUST (by necessity) be written in Lua. See http://rpm.org/user_doc/lua.html for more information.

Writing Scriptlets

Some tips for writing good scriptlets

Saving state between scriptlets

Sometimes a scriptlet needs to save some state from an earlier running scriptlet in order to use it at a later running scriptlet. This is especially common when trying to optimize the scriptlets. Examples:

  • If a %posttrans needs to de-register some piece of information when upgrading but the file that has that information is removed when the old package is removed the scriptlets need to save that file during %pre or %post so that the script in %posttrans can access it.
  • If we only want the program in %posttrans to do its work once per-transaction, we may need to write out a flag file so that the %posttrans knows whether to perform an action.

To address these issues scriptlets that run earlier need to write out information that is used in %posttrans. We recommend using a subdirectory of %{_localstatedir}/lib/rpm-state/ for that. For instance, the eclipse plugin scripts touch a file in %{_localstatedir}/lib/rpm-state/eclipse/ when they're installed. The %posttrans runs a script that checks if that file exists. If it does, it performs its action and then deletes the file. That way the script only performs its action once per transaction.


If RPM file triggers are not appropriate, complex scriptlets which are shared between multiple packages MAY be placed in RPM macros. This has two benefits:

  • The standard package authors only have to remember the macros, not the complex stuff that it does
  • The macros' implementations may change without having to update the package

When writing the macros, the FPC will still want to review the macros (and perhaps include the implementation of the macros in the guideline to show packagers what's happening behind the scenes).

One principle that the FPC follows is that macros generally don't contain the start of scriptlet tags (for instance, %pre) because this makes it difficult to do additional work in the scriptlet. This also means that a single macro can not be defined to do things in both %pre and %post. Instead, write one macro that performs the actions in %pre and a separate macro that performs the actions in %post. This principle makes it so that all spec files can use your macros in the same manner even if they already have a %pre or %post defined.

Of course, in the above situation it is better to use RPM file triggers if at all possible.


Shared libraries

Installing shared libraries requires running /sbin/ldconfig to update the dynamic linker's cache files. These can be invoked like:


It is also common to invoke these with the '-p' option as they are often the only program invoked in a scriptlet:

%post -p /sbin/ldconfig
%postun -p /sbin/ldconfig

If applicable, the latter way is recommended because doing so will automatically add appropriate dependencies on /sbin/ldconfig to the package (and FWIW, will prevent unnecessarily launching a shell process in the scriptlets).

Users and groups

These are discussed on a separate page



GConf is a configuration scheme currently used by the GNOME desktop. Programs which use it setup default values in a [NAME] .schemas file which is installed under %{_sysconfdir}/gconf/schemas/[NAME] .schemas. These defaults are then registered with the gconf daemon which monitors the configuration values and alerts applications when values the applications are interested in change. The schema files also provide documentation about what each value in the configuration system means (which gets displayed when you browse the database in the gconf-editor program).

For packaging purposes, we have to disable schema installation during build, and also register the values in the [NAME] .schemas file with the gconf daemon on installation and unregister them on removal. Due to the ordering of the scriptlets, this is a four step process.

Disabling the GConf installation during the package creation can be done like so:


The GCONF_DISABLE_MAKEFILE_SCHEMA_INSTALL environment variable suppresses the installation of the schema during the building of the package. An alternative for some packages is to pass a configure flag:

%configure --disable-schemas

Unfortunately, this configure switch only works if the upstream packager has adapted their Makefile.am to handle it. If the Makefile.am is not configured, this switch won't do anything and you'll need to use the environment variable instead.

Here's the second part:

BuildRequires: GConf2
Requires(pre): GConf2
Requires(post): GConf2
Requires(preun): GConf2
%gconf_schema_prepare schema1 schema2
%gconf_schema_obsolete schema3

In this section we uninstall old schemas during upgrade using one of two macros.

%gconf_schema_prepare is used for any current GConf schemas. It takes care of uninstalling previous versions of schemas that this package currently installs. It takes a space separated list of schema names without path or suffix that the package installs. Note that behind the scenes, this macro works with the %post scriptlet to only process GConf schemas if changes have occurred.

%gconf_schema_obsolete is used for schemas that this package previously provided but no longer does. It will deregister the old schema if it is present on the system. Nothing will happen if the old schema is not present. This macro takes a space separated list of schemas to uninstall. One example of using this might be if the package changed names. If the old schema was named foo.schemas and the new schema is named foobar.schemas you'd use:

%gconf_schema_prepare foobar
%gconf_schema_obsolete foo

The next section does the processing of the newly installed schemas:

%gconf_schema_upgrade schema1 schema2

%gconf_schema_upgrade takes a space separated list of schemas that the package currently installs just like %gconf_schema_prepare. Behind the scenes, it does the actual work of registering the new version of the schema and deregistering the old version.

The last section is for unregistering schemas when a package is removed:

%gconf_schema_remove schema1 schema2

When a package is upgraded rpm invokes the %pre scriptlet to register and deregister the schemas. When a package is uninstalled, the %preun scriptlet is used. %gconf_schema_remove takes the list of schemas that this package currently provides and removes them for us.

Rebuilds for changes to macros

When macros change, packages that make use of them have to be rebuilt to pick up the changes. This repoquery command can be used to find the schema including packages to rebuild:

repoquery --whatprovides "/etc/gconf/schemas/*" |sort |uniq |wc -l

EPEL Notes

EPEL does not have macros.gconf2, so please follow the instructions found here: Packaging:EPEL#GConf


The GNU project and many other programs use the texinfo file format for much of its documentation. These info files are usually located in /usr/share/info/. When installing or removing a package, install-info from the info package takes care of adding the newly installed files to the main info index and removing them again on deinstallation.

Requires(post): info
Requires(preun): info
/sbin/install-info %{_infodir}/%{name}.info %{_infodir}/dir || :

if [ $1 = 0 ] ; then
  /sbin/install-info --delete %{_infodir}/%{name}.info %{_infodir}/dir || :

These two scriptlets tell install-info to add entries for the info pages to the main index file on installation and remove them at erase time. The "|| :" in this case prevents failures that would typically affect systems that have been configured not to install any %doc files, or have read-only mounted, %_netsharedpath /usr/share.


F24 only
This scriptlet SHOULD NOT be used in Fedora 25 or later.

Use this when a desktop entry has a 'MimeType key.

/usr/bin/update-desktop-database &> /dev/null || :

/usr/bin/update-desktop-database &> /dev/null || :

Note: This scriptlet follows the same convention as mimeinfo files and gtk-icon-cache. Namely, the spec file should not Require desktop-file-utils for this. For older releases, one should

Requires(post): desktop-file-utils
Requires(postun): desktop-file-utils

(See http://bugzilla.redhat.com/180898 and http://bugzilla.redhat.com/180899)

Icon Cache

If an application installs icons into one of the subdirectories in %{_datadir}/icons/ (such as hicolor in the following examples), icon caches must be updated so that the installed icons show up in menus right after package installation. This consists of updating the timestamp of the top-level icon directory where the icons were installed, and running gtk-update-icon-cache. 'touch'ing the top-level dir is done so that environments compatible with the Icon theme specification can refresh their caches, and gtk-update-icon-cache which is additionally required for GNOME also does its work based on the dir timestamp.

Note that no dependencies should be added for this. If gtk-update-icon-cache is not available, there's nothing that would be needing the cache update, ditto if "touch" is not available, there's nothing that would benefit from icon cache updates installed yet either. Not adding the dependency on gtk-update-icon-cache (ie. gtk2 >= 2.6.0) or "touch" makes it easier to use the package (or the same specfile) on systems where it's not available nor needed, such as older distro versions or (very) trimmed down installations, and generally results in less entries in specfiles, rpmdb, and repo metadatas.

/bin/touch --no-create %{_datadir}/icons/hicolor &>/dev/null || :

if [ $1 -eq 0 ] ; then
    /bin/touch --no-create %{_datadir}/icons/hicolor &>/dev/null
    /usr/bin/gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :

/usr/bin/gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :


Packages containing systemd unit files need to use scriptlets to ensure proper handling of those services. Services can either be enabled or disabled by default. To determine which case your specific service falls into, please refer to FESCo's policy here: Packaging:DefaultServices. On upgrade, a package may only restart a service if it is running; it may not start it if it is off. Also, the service may not enable itself if it is currently disabled.


The systemd package provides a set of helper macros to handle systemd scriptlet operations. These macros support systemd "presets", as documented in Features/PackagePresets. The %systemd_requires macro is a shortcut for listing the per-scriptlet dependencies on systemd.

BuildRequires: systemd

%systemd_post apache-httpd.service

%systemd_preun apache-httpd.service

%systemd_postun_with_restart apache-httpd.service

Some services do not support being restarted (e.g. D-Bus and various storage daemons). If your service should not be restarted upon upgrade, then use the following %postun scriptlet instead of the one shown above:

%systemd_postun apache-httpd.service

If your package includes one or more systemd units that need to be enabled by default on package installation, they MUST be covered by the Fedora preset policy.

If a package is suitable for installation without systemd (in a container image, for example) and does not require any of the systemd mechanisms such as tmpfiles.d, then the %systemd_ordering macro MAY be used instead of the %systemd_requires macro.

User units

There are additional macros for user units (those installed under %_userunitdir) that should be used similarly to those for system units. These enable and disable user units according to presets, and are %systemd_user_post (to be used in %post) and %systemd_user_preun (to be used in %preun).

BuildRequires: systemd

%systemd_user_post %{name}.service

%systemd_user_preun %{name}.service
Macro details

For details on what these macros evaluate to, refer to the following sources:
https://github.com/systemd/systemd/blob/master/src/core/triggers.systemd.in and


/etc/shells is a text file which controls whether an application can be used as a system login shell of users. It contains the set of valid shells which can be used in the system. If you are packaging a new shell, you need to add entries to this file that reference the added shells. See: man 5 SHELLS for more information.

As this file can be edited by sysadmins, we need to first determine if relevant lines are already in the file. If they don't already exist then we just need to echo the shell's binary path to the file. Since the UsrMove Feature in Fedora 17 made /bin a symlink to /usr/bin we need to place both paths into the /etc/shells file. Here is an example of the scriptlet to package with shell named "foo":

if [ "$1" = 1 ]; then
  if [ ! -f %{_sysconfdir}/shells ] ; then
    echo "%{_bindir}/foo" > %{_sysconfdir}/shells
    echo "/bin/foo" >> %{_sysconfdir}/shells
    grep -q "^%{_bindir}/foo$" %{_sysconfdir}/shells || echo "%{_bindir}/foo" >> %{_sysconfdir}/shells
    grep -q "^/bin/foo$" %{_sysconfdir}/shells || echo "/bin/foo" >> %{_sysconfdir}/shells

if [ "$1" = 0 ] && [ -f %{_sysconfdir}/shells ] ; then
  sed -i '\!^%{_bindir}/foo$!d' %{_sysconfdir}/shells
  sed -i '\!^/bin/foo$!d' %{_sysconfdir}/shells