tmpfiles.d

TMPFILES.D(5)                      tmpfiles.d                      TMPFILES.D(5)



NAME
       tmpfiles.d - Configuration for creation, deletion and cleaning of
       volatile and temporary files

SYNOPSIS
       /etc/tmpfiles.d/*.conf
       /run/tmpfiles.d/*.conf
       /usr/lib/tmpfiles.d/*.conf


       ~/.config/user-tmpfiles.d/*.conf
       $XDG_RUNTIME_DIR/user-tmpfiles.d/*.conf
       ~/.local/share/user-tmpfiles.d/*.conf
       ...
       /usr/share/user-tmpfiles.d/*.conf



       #Type Path                                     Mode User Group Age         Argument
       f     /file/to/create                          mode user group -           content
       f+    /file/to/create-or-truncate              mode user group -           content
       w     /file/to/write-to                        -    -    -     -           content
       w+    /file/to/append-to                       -    -    -     -           content
       d     /directory/to/create-and-cleanup         mode user group cleanup-age -
       D     /directory/to/create-and-remove          mode user group cleanup-age -
       e     /directory/to/cleanup                    mode user group cleanup-age -
       v     /subvolume-or-directory/to/create        mode user group -           -
       q     /subvolume-or-directory/to/create        mode user group -           -
       Q     /subvolume-or-directory/to/create        mode user group -           -
       p     /fifo/to/create                          mode user group -           -
       p+    /fifo/to/[re]create                      mode user group -           -
       L     /symlink/to/create                       -    -    -     -           symlink/target/path
       L+    /symlink/to/[re]create                   -    -    -     -           symlink/target/path
       c     /dev/char-device-to-create               mode user group -           major:minor
       c+    /dev/char-device-to-[re]create           mode user group -           major:minor
       b     /dev/block-device-to-create              mode user group -           major:minor
       b+    /dev/block-device-to-[re]create          mode user group -           major:minor
       C     /target/to/create                        -    -    -     -           /source/to/copy
       x     /path-or-glob/to/ignore                  -    -    -     -           -
       X     /path-or-glob/to/ignore/recursively      -    -    -     -           -
       r     /empty/dir/to/remove                     -    -    -     -           -
       R     /dir/to/remove/recursively               -    -    -     -           -
       z     /path-or-glob/to/adjust/mode             mode user group -           -
       Z     /path-or-glob/to/adjust/mode/recursively mode user group -           -
       t     /path-or-glob/to/set/xattrs              -    -    -     -           xattrs
       T     /path-or-glob/to/set/xattrs/recursively  -    -    -     -           xattrs
       h     /path-or-glob/to/set/attrs               -    -    -     -           file attrs
       H     /path-or-glob/to/set/attrs/recursively   -    -    -     -           file attrs
       a     /path-or-glob/to/set/acls                -    -    -     -           POSIX ACLs
       a+    /path-or-glob/to/append/acls             -    -    -     -           POSIX ACLs
       A     /path-or-glob/to/set/acls/recursively    -    -    -     -           POSIX ACLs
       A+    /path-or-glob/to/append/acls/recursively -    -    -     -           POSIX ACLs


DESCRIPTION
       tmpfiles.d configuration files provide a generic mechanism to define the
       creation of regular files, directories, pipes, and device nodes,
       adjustments to their access mode, ownership, attributes, quota
       assignments, and contents, and finally their time-based removal. It is
       mostly commonly used for volatile and temporary files and directories
       (such as those located under /run/, /tmp/, /var/tmp/, the API file
       systems such as /sys/ or /proc/, as well as some other directories below
       /var/).

       systemd-tmpfiles uses this configuration to create volatile files and
       directories during boot and to do periodic cleanup afterwards. See
       systemd-tmpfiles(5) for the description of
       systemd-tmpfiles-setup.service, systemd-tmpfiles-clean.service, and
       associated units.

       System daemons frequently require private runtime directories below /run/
       to store communication sockets and similar. For these, it is better to
       use RuntimeDirectory= in their unit files (see systemd.exec(5) for
       details), if the flexibility provided by tmpfiles.d is not required. The
       advantages are that the configuration required by the unit is centralized
       in one place, and that the lifetime of the directory is tied to the
       lifetime of the service itself. Similarly, StateDirectory=,
       CacheDirectory=, LogsDirectory=, and ConfigurationDirectory= should be
       used to create directories under /var/lib/, /var/cache/, /var/log/, and
       /etc/.  tmpfiles.d should be used for files whose lifetime is independent
       of any service or requires more complicated configuration.

CONFIGURATION DIRECTORIES AND PRECEDENCE
       Each 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 (note that lines
       suppressed due to the "!"  are filtered before application, meaning that
       if an early line carries the exclamation mark and is suppressed because
       of that, a later line matching in path will be applied). All other
       conflicting entries will be logged as errors. When two lines are prefix
       path and suffix path of each other, then the prefix line is always
       created first, the suffix later (and if removal applies to the line, the
       order is reversed: the suffix is removed first, the prefix later). Lines
       that take globs are applied after those accepting no globs. If multiple
       operations shall be applied on the same file (such as ACL, xattr, file
       attribute adjustments), these are always done in the same fixed order.
       Except for those cases, 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.

CONFIGURATION FILE FORMAT
       The configuration format is one line per path containing type, path,
       mode, ownership, age, and argument fields:

           #Type Path        Mode User Group Age Argument
           d     /run/user   0755 root root  10d -
           L     /tmp/foobar -    -    -     -   /dev/null

       Fields may be enclosed within quotes and contain C-style escapes.

   Type
       The type consists of a single letter and optionally an exclamation mark
       ("!") and/or minus sign ("-").

       The following line types are understood:

       f, f+
           f will create a file if it does not exist yet. If the argument
           parameter is given and the file did not exist yet, it will be written
           to the file.  f+ will create or truncate the file. If the argument
           parameter is given, it will be written to the file. Does not follow
           symlinks.

       w, w+
           Write the argument parameter to a file, if the file exists. If
           suffixed with +, the line will be appended to the file. If your
           configuration writes multiple lines to the same file, use w+. 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.

       d
           Create a directory. The mode and ownership will be adjusted if
           specified. Contents of this directory are subject to time based
           cleanup if the age argument is specified.

       D
           Similar to d, but in addition the contents of the directory will be
           removed when --remove is used.

       e
           Adjust the mode and ownership of existing directories and remove
           their contents based on age. Lines of this type accept shell-style
           globs in place of normal path names. Contents of the directories are
           subject to time based cleanup if the age argument is specified. If
           the age argument is "0", contents will be unconditionally deleted
           every time systemd-tmpfiles --clean is run.

           For this entry to be useful, at least one of the mode, user, group,
           or age arguments must be specified, since otherwise this entry has no
           effect. As an exception, an entry with no effect may be useful when
           combined with !, see the examples.

       v
           Create a subvolume if the path does not exist yet, the file system
           supports subvolumes (btrfs), and the system itself is installed into
           a subvolume (specifically: the root directory / is itself a
           subvolume). Otherwise, create a normal directory, in the same way as
           d.

           A subvolume created with this line type is not assigned to any
           higher-level quota group. For that, use q or Q, which allow creating
           simple quota group hierarchies, see below.

       q
           Create a subvolume or directory the same as v, but assign the
           subvolume to the same higher-level quota groups as the parent. This
           ensures that higher-level limits and accounting applied to the parent
           subvolume also include the specified subvolume. On non-btrfs file
           systems, this line type is identical to d.

           If the subvolume already exists, no change to the quota hierarchy is
           made, regardless of whether the subvolume is already attached to a
           quota group or not. Also see Q below. See btrfs-qgroup(8) for details
           about the btrfs quota group concept.

       Q
           Create the subvolume or directory the same as v, but assign the new
           subvolume to a new leaf quota group. Instead of copying the
           higher-level quota group assignments from the parent as is done with
           q, the lowest quota group of the parent subvolume is determined that
           is not the leaf quota group. Then, an "intermediary" quota group is
           inserted that is one level below this level, and shares the same ID
           part as the specified subvolume. If no higher-level quota group
           exists for the parent subvolume, a new quota group at level 255
           sharing the same ID as the specified subvolume is inserted instead.
           This new intermediary quota group is then assigned to the parent
           subvolume's higher-level quota groups, and the specified subvolume's
           leaf quota group is assigned to it.

           Effectively, this has a similar effect as q, however introduces a new
           higher-level quota group for the specified subvolume that may be used
           to enforce limits and accounting to the specified subvolume and
           children subvolume created within it. Thus, by creating subvolumes
           only via q and Q, a concept of "subtree quotas" is implemented. Each
           subvolume for which Q is set will get a "subtree" quota group
           created, and all child subvolumes created within it will be assigned
           to it. Each subvolume for which q is set will not get such a
           "subtree" quota group, but it is ensured that they are added to the
           same "subtree" quota group as their immediate parents.

           It is recommended to use Q for subvolumes that typically contain
           further subvolumes, and where it is desirable to have accounting and
           quota limits on all child subvolumes together. Examples for Q are
           typically /home/ or /var/lib/machines/. In contrast, q should be used
           for subvolumes that either usually do not include further subvolumes
           or where no accounting and quota limits are needed that apply to all
           child subvolumes together. Examples for q are typically /var/ or
           /var/tmp/.

           As with q, Q has no effect on the quota group hierarchy if the
           subvolume already exists, regardless of whether the subvolume already
           belong to a quota group or not.

       p, p+
           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.

       L, L+
           Create a symlink if it does not exist yet. If suffixed with + and a
           file or directory 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. Note that permissions and
           ownership on symlinks are ignored.

       c, c+
           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.

       b, b+
           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.

       C
           Recursively copy a file or directory, if the destination files or
           directories do not exist yet or the destination directory is empty.
           Note that this command will not descend into subdirectories if the
           destination directory already exists and is not empty. 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.

       x
           Ignore 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.

       X
           Ignore 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.

       r
           Remove 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.

       R
           Recursively 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.

       z
           Adjust the access mode, user and group ownership, 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.

       Z
           Recursively set the access mode, user and group ownership, 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.

       t
           Set extended attributes, see attr(5) for details. The argument field
           should take one or more assignment expressions in the form
           namespace.attribute=value, for examples see below. 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.

           Please note that extended attributes settable with this line type are
           a different concept from the Linux file attributes settable with h/H,
           see below.

       T
           Same as t, but operates recursively.

       h
           Set Linux file/directory attributes. Lines of this type accept
           shell-style globs in place of normal path names.

           The format of the argument field is [+-=][aAcCdDeijPsStTu]. The
           prefix + (the default one) causes the attribute(s) to be added; -
           causes the attribute(s) to be removed; = causes the attributes to be
           set exactly as the following letters. The letters "aAcCdDeijPsStTu"
           select the new attributes for the files, see chattr(1) 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.

           Please note that the Linux file attributes settable with this line
           type are a different concept from the extended attributes settable
           with t/T, see above.

       H
           Sames as h, but operates recursively.

       a, a+
           Set POSIX ACLs (access control lists), see acl(5). If suffixed with
           +, the 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 explicitly 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.

       A, A+
           Same as a and a+, but recursive. Does not follow symlinks.

       If the exclamation mark ("!") is used, this line is only safe to 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 take lines with an exclamation
       mark only into consideration, if the --boot 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 --boot.

       If the minus sign ("-") is used, this line failing to run successfully
       during create (and only create) will not cause the execution of
       systemd-tmpfiles to return an error.

       For example:

           # Modify sysfs but don't fail if we are in a container with a read-only /proc
           w- /proc/sys/vm/swappiness - - - - 10

       Note that for all line types that result in creation of any kind of file
       node (i.e.  f/F, d/D/v/q/Q, p, L, c/b and C) leading directories are
       implicitly created if needed, owned by root with an access mode of 0755.
       In order to create them with different modes or ownership make sure to
       add appropriate d lines.

   Path
       The file system path specification supports simple specifier expansion,
       see below. The path (after expansion) must be absolute.

   Mode
       The 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.

   User, Group
       The user and group to use for this file or directory. This may either be
       a numeric ID or a user/group name. If omitted or when set to "-", the
       user and group of the user who invokes systemd-tmpfiles is used. For z
       and 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.

       This field should generally only reference system users/groups, i.e.
       users/groups that are guaranteed to be resolvable during early boot. If
       this field references users/groups that only become resolveable during
       later boot (i.e. after NIS, LDAP or a similar networked directory service
       become available), execution of the operations declared by the line will
       likely fail. Also see Notes on Resolvability of User and Group Names[1]
       for more information on requirements on system user/group definitions.

   Age
       The 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 suffixes for the respective time units:
       s, m or min, h, d, w, ms, and us, meaning seconds, minutes, hours, days,
       weeks, milliseconds, and microseconds, respectively. 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, e, v, q, Q, C, x
       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.

       The age of a file system entry is determined from its last modification
       timestamp (mtime), its last access timestamp (atime), and (except for
       directories) its last status change timestamp (ctime). Any of these three
       (or two) values will prevent cleanup if it is more recent than the
       current time minus the age field.

       Note that while the aging algorithm is run a 'shared' BSD file lock (see
       flock(2)) is taken on each directory the algorithm descends into (and
       each directory below that, and so on). If the aging algorithm finds a
       lock is already taken on some directory, it (and everything below it) is
       skipped. Applications may use this to temporarily exclude certain
       directory subtrees from the aging algorithm: the applications can take a
       BSD file lock themselves, and as long as they keep it aging of the
       directory and everything below it is disabled.

   Argument
       For L lines determines the destination path of the symlink. For c and 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,
       the argument 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 and T, determines extended attributes to be set. For a
       and A, determines ACL attributes to be set. For h and H, determines the
       file attributes to set. Ignored for all other lines.

       This field can contain specifiers, see below.

SPECIFIERS
       Specifiers can be used in the "path" and "argument" fields. An unknown or
       unresolvable specifier is treated as invalid configuration. The following
       expansions are understood:

       Table 1. Specifiers available
       ┌──────────┬──────────────────────┬────────────────────────┐
       │Specifier Meaning              Details                │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%a"      │ Architecture         │ A short string         │
       │          │                      │ identifying the        │
       │          │                      │ architecture of the    │
       │          │                      │ local system. A        │
       │          │                      │ string such as x86,    │
       │          │                      │ x86-64 or arm64. See   │
       │          │                      │ the architectures      │
       │          │                      │ defined for            │
       │          │                      │ ConditionArchitecture= │
       │          │                      │ in systemd.unit(5)     │
       │          │                      │ for a full list.       │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%b"      │ Boot ID              │ The boot ID of the     │
       │          │                      │ running system,        │
       │          │                      │ formatted as string.   │
       │          │                      │ See random(4) for more │
       │          │                      │ information.           │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%B"      │ Operating system     │ The operating system   │
       │          │ build ID             │ build identifier of    │
       │          │                      │ the running system, as │
       │          │                      │ read from the          │
       │          │                      │ BUILD_ID= field of     │
       │          │                      │ /etc/os-release. If    │
       │          │                      │ not set, resolves to   │
       │          │                      │ an empty string. See   │
       │          │                      │ os-release(5) for more │
       │          │                      │ information.           │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%C"      │ System or user cache │ In --user mode, this   │
       │          │ directory            │ is the same as         │
       │          │                      │ $XDG_CACHE_HOME, and   │
       │          │                      │ /var/cache otherwise.  │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%g"      │ User group           │ This is the name of    │
       │          │                      │ the group running the  │
       │          │                      │ command. In case of    │
       │          │                      │ the system instance    │
       │          │                      │ this resolves to       │
       │          │                      │ "root".                │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%G"      │ User GID             │ This is the numeric    │
       │          │                      │ GID of the group       │
       │          │                      │ running the command.   │
       │          │                      │ In case of the system  │
       │          │                      │ instance this resolves │
       │          │                      │ to 0.                  │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%h"      │ User home directory  │ This is the home       │
       │          │                      │ directory of the user  │
       │          │                      │ running the command.   │
       │          │                      │ In case of the system  │
       │          │                      │ instance this resolves │
       │          │                      │ to "/root".            │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%H"      │ Host name            │ The hostname of the    │
       │          │                      │ running system.        │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%l"      │ Short host name      │ The hostname of the    │
       │          │                      │ running system,        │
       │          │                      │ truncated at the first │
       │          │                      │ dot to remove any      │
       │          │                      │ domain component.      │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%L"      │ System or user log   │ In --user mode, this   │
       │          │ directory            │ is the same as         │
       │          │                      │ $XDG_CONFIG_HOME with  │
       │          │                      │ /log appended, and     │
       │          │                      │ /var/log otherwise.    │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%m"      │ Machine ID           │ The machine ID of the  │
       │          │                      │ running system,        │
       │          │                      │ formatted as string.   │
       │          │                      │ See machine-id(5) for  │
       │          │                      │ more information.      │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%o"      │ Operating system ID  │ The operating system   │
       │          │                      │ identifier of the      │
       │          │                      │ running system, as     │
       │          │                      │ read from the ID=      │
       │          │                      │ field of               │
       │          │                      │ /etc/os-release. See   │
       │          │                      │ os-release(5) for more │
       │          │                      │ information.           │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%S"      │ System or user state │ In --user mode, this   │
       │          │ directory            │ is the same as         │
       │          │                      │ $XDG_CONFIG_HOME, and  │
       │          │                      │ /var/lib otherwise.    │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%t"      │ System or user       │ In --user mode, this   │
       │          │ runtime directory    │ is the same            │
       │          │                      │ $XDG_RUNTIME_DIR, and  │
       │          │                      │ /run/ otherwise.       │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%T"      │ Directory for        │ This is either /tmp or │
       │          │ temporary files      │ the path "$TMPDIR",    │
       │          │                      │ "$TEMP" or "$TMP" are  │
       │          │                      │ set to. (Note that the │
       │          │                      │ directory may be       │
       │          │                      │ specified without a    │
       │          │                      │ trailing slash.)       │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%u"      │ User name            │ This is the name of    │
       │          │                      │ the user running the   │
       │          │                      │ command. In case of    │
       │          │                      │ the system instance    │
       │          │                      │ this resolves to       │
       │          │                      │ "root".                │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%U"      │ User UID             │ This is the numeric    │
       │          │                      │ UID of the user        │
       │          │                      │ running the command.   │
       │          │                      │ In case of the system  │
       │          │                      │ instance this resolves │
       │          │                      │ to 0.                  │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%v"      │ Kernel release       │ Identical to uname -r  │
       │          │                      │ output.                │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%V"      │ Directory for larger │ This is either         │
       │          │ and persistent       │ /var/tmp or the path   │
       │          │ temporary files      │ "$TMPDIR", "$TEMP" or  │
       │          │                      │ "$TMP" are set to.     │
       │          │                      │ (Note that the         │
       │          │                      │ directory may be       │
       │          │                      │ specified without a    │
       │          │                      │ trailing slash.)       │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%w"      │ Operating system     │ The operating system   │
       │          │ version ID           │ version identifier of  │
       │          │                      │ the running system, as │
       │          │                      │ read from the          │
       │          │                      │ VERSION_ID= field of   │
       │          │                      │ /etc/os-release. If    │
       │          │                      │ not set, resolves to   │
       │          │                      │ an empty string. See   │
       │          │                      │ os-release(5) for more │
       │          │                      │ information.           │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%W"      │ Operating system     │ The operating system   │
       │          │ variant ID           │ variant identifier of  │
       │          │                      │ the running system, as │
       │          │                      │ read from the          │
       │          │                      │ VARIANT_ID= field of   │
       │          │                      │ /etc/os-release. If    │
       │          │                      │ not set, resolves to   │
       │          │                      │ an empty string. See   │
       │          │                      │ os-release(5) for more │
       │          │                      │ information.           │
       ├──────────┼──────────────────────┼────────────────────────┤
       │"%%"      │ Single percent sign  │ Use "%%" in place of   │
       │          │                      │ "%" to specify a       │
       │          │                      │ single percent sign.   │
       └──────────┴──────────────────────┴────────────────────────┘

EXAMPLES
       Example 1. Create directories with specific mode and ownership

       screen(1), needs two directories created at boot with specific modes and
       ownership:

           # /usr/lib/tmpfiles.d/screen.conf
           d /run/screens  1777 root screen 10d
           d /run/uscreens 0755 root screen 10d12h

       Contents of /run/screens and /run/uscreens will be cleaned up after 10
       and 10½ days, respectively.

       Example 2. Create a directory with a SMACK attribute

           D /run/cups - - - -
           t /run/cups - - - - security.SMACK64=printing user.attr-with-spaces="foo bar"


       The directory will be owned by root and have default mode. Its contents
       are not subject to time based cleanup, but will be obliterated when
       systemd-tmpfiles --remove runs.

       Example 3. Create a directory and prevent its contents from cleanup

       abrt(1), needs a directory created at boot with specific mode and
       ownership and its content should be preserved from the automatic cleanup
       applied to the contents of /var/tmp:

           # /usr/lib/tmpfiles.d/tmp.conf
           d /var/tmp 1777 root root 30d

           # /usr/lib/tmpfiles.d/abrt.conf
           d /var/tmp/abrt 0755 abrt abrt -

       Example 4. Apply clean up during boot and based on time

           # /usr/lib/tmpfiles.d/dnf.conf
           r! /var/cache/dnf/*/*/download_lock.pid
           r! /var/cache/dnf/*/*/metadata_lock.pid
           r! /var/lib/dnf/rpmdb_lock.pid
           e  /var/cache/dnf/ - - - 30d

       The lock files will be removed during boot. Any files and directories in
       /var/cache/dnf/ will be removed after they have not been accessed in 30
       days.

       Example 5. Empty the contents of a cache directory on boot

           # /usr/lib/tmpfiles.d/krb5rcache.conf
           e! /var/cache/krb5rcache - - - 0

       Any files and subdirectories in /var/cache/krb5rcache/ will be removed on
       boot. The directory will not be created.

/RUN/ AND /VAR/RUN/
       /var/run/ is a deprecated symlink to /run/, and applications should use
       the latter.  systemd-tmpfiles will warn if /var/run/ is used.

SEE ALSO
       systemd(1), systemd-tmpfiles(8), systemd-delta(1), systemd.exec(5),
       attr(5), getfattr(1), setfattr(1), setfacl(1), getfacl(1), chattr(1),
       btrfs-subvolume(8), btrfs-qgroup(8)

NOTES
        1. Notes on Resolvability of User and Group Names
           https://systemd.io/UIDS-GIDS/#notes-on-resolvability-of-user-and-group-names



systemd 247                                                        TMPFILES.D(5)