tmpfiles.dsystemdDocumentationBrandonPhilipsbrandon@ifup.orgtmpfiles.d5tmpfiles.dConfiguration for creation, deletion and cleaning of
volatile and temporary files/etc/tmpfiles.d/*.conf/run/tmpfiles.d/*.conf/usr/lib/tmpfiles.d/*.confDescriptionsystemd-tmpfiles uses the configuration
files from the above directories to describe the creation,
cleaning and removal of volatile and temporary files and
directories which usually reside in directories such as
/run or /tmp.Volatile and temporary files and directories are those
located in /run (and its alias
/var/run), /tmp,
/var/tmp, the API file systems such as
/sys or /proc, as well
as some other directories below /var.System daemons frequently require private runtime
directories below /run to place communication
sockets and similar in. For these, consider declaring them in
their unit files using RuntimeDirectory= (see
systemd.exec5
for details), if this is feasible.Configuration FormatEach configuration file shall be named in the style of
package.conf or
package-part.conf.
The second variant should be used when it is desirable to make it
easy to override just this part of configuration.Files in /etc/tmpfiles.d override files
with the same name in /usr/lib/tmpfiles.d and
/run/tmpfiles.d. Files in
/run/tmpfiles.d override files with the same
name in /usr/lib/tmpfiles.d. Packages should
install their configuration files in
/usr/lib/tmpfiles.d. Files in
/etc/tmpfiles.d are reserved for the local
administrator, who may use this logic to override the
configuration files installed by vendor packages. All
configuration files are sorted by their filename in lexicographic
order, regardless of which of the directories they reside in. If
multiple files specify the same path, the entry in the file with
the lexicographically earliest name will be applied. All other
conflicting entries will be logged as errors. When two lines are
prefix and suffix of each other, then the prefix is always
processed first, the suffix later. Otherwise, the
files/directories are processed in the order they are
listed.If the administrator wants to disable a configuration file
supplied by the vendor, the recommended way is to place a symlink
to /dev/null in
/etc/tmpfiles.d/ bearing the same filename.
The configuration format is one line per path containing
type, path, mode, ownership, age, and argument fields:#Type Path Mode UID GID Age Argument
d /run/user 0755 root root 10d -
L /tmp/foobar - - - - /dev/nullFields may be enclosed within quotes and contain C-style escapes.TypeThe type consists of a single letter and optionally an
exclamation mark.The following line types are understood:fCreate a file if it does not exist yet. If
the argument parameter is given, it will be written to the
file. Does not follow symlinks.FCreate or truncate a file. If the argument
parameter is given, it will be written to the file. Does not follow symlinks.wWrite the argument parameter to a file, if
the file exists. Lines of this type accept shell-style
globs in place of normal path names. The argument parameter
will be written without a trailing newline. C-style
backslash escapes are interpreted. Follows
symlinks.dCreate a directory if it does not exist yet.
DCreate or empty a directory.vCreate a subvolume if the path does not
exist yet and the file system supports this
(btrfs). Otherwise create a normal directory, in the same
way as d.pp+Create a named pipe (FIFO) if it does not
exist yet. If suffixed with + and a file
already exists where the pipe is to be created, it will be
removed and be replaced by the pipe.LL+Create a symlink if it does not exist
yet. If suffixed with + and a file
already exists where the symlink is to be created, it will
be removed and be replaced by the symlink. If the argument
is omitted, symlinks to files with the same name residing in
the directory /usr/share/factory/ are
created.cc+Create a character device node if it does
not exist yet. If suffixed with + and a
file already exists where the device node is to be created,
it will be removed and be replaced by the device node. It is
recommended to suffix this entry with an exclamation mark to
only create static device nodes at boot, as udev will not
manage static device nodes that are created at runtime.
bb+Create a block device node if it does not
exist yet. If suffixed with + and a file
already exists where the device node is to be created, it
will be removed and be replaced by the device node. It is
recommended to suffix this entry with an exclamation mark to
only create static device nodes at boot, as udev will not
manage static device nodes that are created at runtime.
CRecursively copy a file or directory, if the
destination files or directories do not exist yet. Note that
this command will not descend into subdirectories if the
destination directory already exists. Instead, the entire
copy operation is skipped. If the argument is omitted, files
from the source directory
/usr/share/factory/ with the same name
are copied. Does not follow symlinks.xIgnore a path during cleaning. Use this type
to exclude paths from clean-up as controlled with the Age
parameter. Note that lines of this type do not influence the
effect of r or R
lines. Lines of this type accept shell-style globs in place
of normal path names. XIgnore a path during cleaning. Use this type
to exclude paths from clean-up as controlled with the Age
parameter. Unlike x, this parameter will
not exclude the content if path is a directory, but only
directory itself. Note that lines of this type do not
influence the effect of r or
R lines. Lines of this type accept
shell-style globs in place of normal path names.
rRemove a file or directory if it exists.
This may not be used to remove non-empty directories, use
R for that. Lines of this type accept
shell-style globs in place of normal path
names. Does not follow symlinks.RRecursively remove a path and all its
subdirectories (if it is a directory). Lines of this type
accept shell-style globs in place of normal path
names. Does not follow symlinks.zAdjust the access mode, group and user, and
restore the SELinux security context of a file or directory,
if it exists. Lines of this type accept shell-style globs in
place of normal path names. Does not follow symlinks.ZRecursively set the access mode, group and
user, and restore the SELinux security context of a file or
directory if it exists, as well as of its subdirectories and
the files contained therein (if applicable). Lines of this
type accept shell-style globs in place of normal path
names. Does not follow symlinks. tSet extended attributes. Lines of this type
accept shell-style globs in place of normal path names.
This can be useful for setting SMACK labels. Does not follow
symlinks.TRecursively set extended attributes. Lines
of this type accept shell-style globs in place of normal
path names. This can be useful for setting SMACK
labels. Does not follow symlinks. hSet file/directory attributes. Lines of this type
accept shell-style globs in place of normal path names.The format of the argument field is [+-=][aAcCdDeijsStTu]
The prefix + (the default one) causes the
attribute(s) to be added; - causes the
attribute(s) to be removed; =
causes the attributes to set exactly as the following letters.The letters aAcCdDeijsStTu select the new
attributes for the files, see
chattr1 for further information.
Passing only = as argument,
resets all the file attributes listed above. It has to be pointed
out that the = prefix, limits itself to the
attributes corresponding to the letters listed here. All other
attributes will be left untouched.Does not follow symlinks.HRecursively set file/directory attributes. Lines
of this type accept shell-style globs in place of normal
path names. Does not follow symlinks.
aa+Set POSIX ACLs (access control lists). If
suffixed with +, specified entries will
be added to the existing set.
systemd-tmpfiles will automatically add
the required base entries for user and group based on the
access mode of the file, unless base entries already exist
or are explictly specified. The mask will be added if not
specified explicitly or already present. Lines of this type
accept shell-style globs in place of normal path names. This
can be useful for allowing additional access to certain
files. Does not follow symlinks.AA+Same as a and
a+, but recursive. Does not follow
symlinks.If the exclamation mark is used, this line is only safe of
execute during boot, and can break a running system. Lines
without the exclamation mark are presumed to be safe to execute
at any time, e.g. on package upgrades.
systemd-tmpfiles will execute line with an
exclamation mark only if option is
given.For example:
# Make sure these are created by default so that nobody else can
d /tmp/.X11-unix 1777 root root 10d
# Unlink the X11 lock files
r! /tmp/.X[0-9]*-lock
The second line in contrast to the first one would break a
running system, and will only be executed with
.PathThe file system path specification supports simple
specifier expansion. The following expansions are
understood:
Specifiers availableSpecifierMeaningDetails%mMachine IDThe machine ID of the running system, formatted as string. See machine-id5 for more information.%bBoot IDThe boot ID of the running system, formatted as string. See random4 for more information.%HHost nameThe hostname of the running system.%vKernel releaseIdentical to uname -r output.%%Escaped %Single percent sign.
ModeThe file access mode to use when creating this file or
directory. If omitted or when set to -, the
default is used: 0755 for directories, 0644 for all other file
objects. For z, Z lines,
if omitted or when set to -, the file access
mode will not be modified. This parameter is ignored for
x, r,
R, L, t,
and a lines.Optionally, if prefixed with ~, the
access mode is masked based on the already set access bits for
existing file or directories: if the existing file has all
executable bits unset, all executable bits are removed from the
new access mode, too. Similarly, if all read bits are removed
from the old access mode, they will be removed from the new
access mode too, and if all write bits are removed, they will be
removed from the new access mode too. In addition, the
sticky/SUID/SGID bit is removed unless applied to a
directory. This functionality is particularly useful in
conjunction with Z.UID, GIDThe user and group to use for this file or directory. This
may either be a numeric user/group ID or a user or group
name. If omitted or when set to -, the
default 0 (root) is used. For z,
Z lines, when omitted or when set to
-, the file ownership will not be
modified. These parameters are ignored for x,
r, R,
L, t, and
a lines.AgeThe date field, when set, is used to decide what files to
delete when cleaning. If a file or directory is older than the
current time minus the age field, it is deleted. The field
format is a series of integers each followed by one of the
following postfixes for the respective time units:
s,
m or min,
h,
d,
w,
ms,
us,
respectively meaning seconds, minutes, hours, days, weeks,
milliseconds, and microseconds. Full names of the time units can
be used too.
If multiple integers and units are specified, the time
values are summed. If an integer is given without a unit,
s is assumed.
When the age is set to zero, the files are cleaned
unconditionally.The age field only applies to lines
starting with d,
D, and
x. If omitted or set to
-, no automatic clean-up is
done.If the age field starts with a tilde character
~, the clean-up is only applied to files and
directories one level inside the directory specified, but not
the files and directories immediately inside it.ArgumentFor L lines determines the destination
path of the symlink. For c,
b determines the major/minor of the device
node, with major and minor formatted as integers, separated by
:, e.g. 1:3. For
f, F, and
w may be used to specify a short string that
is written to the file, suffixed by a newline. For
C, specifies the source file or
directory. For t, T
determines extended attributes to be set. For
a, A determines ACL
attributes to be set. For h,
H determines the file attributes to
set. Ignored for all other lines.Example/etc/tmpfiles.d/screen.conf examplescreen needs two directories created at
boot with specific modes and ownership.d /run/screens 1777 root root 10d
d /run/uscreens 0755 root root 10d12h
t /run/screen - - - - user.name="John Smith" security.SMACK64=screen/etc/tmpfiles.d/abrt.conf exampleabrt needs a directory created at boot with specific mode and ownership and its content should be preserved.d /var/tmp/abrt 0755 abrt abrt
x /var/tmp/abrt/*See Alsosystemd1,
systemd-tmpfiles8,
systemd-delta1,
systemd.exec5,
attr5,
getfattr1,
setfattr1,
setfacl1,
getfacl1,
chattr1