+ A file or a directory name, without path, that will be ignored,
+ regardless of the location in the mail store directory hierarchy.
+
+ Or:
+
+ A regular expression delimited with // that will be matched
+ against the path of the file or directory relative to the database
+ path. Matching files and directories will be ignored. The
+ beginning and end of string must be explicitly anchored. For
+ example, /.*/foo$/ would match "bar/foo" and "bar/baz/foo", but
+ not "foo" or "bar/foobar".
+
+ Default: empty list.
+
+search.exclude\_tags
+ A list of tags that will be excluded from search results by
+ default. Using an excluded tag in a query will override that
+ exclusion.
+
+ Default: empty list. Note that :any:`notmuch-setup(1)` puts
+ ``deleted;spam`` here when creating new configuration file.
+
+maildir.synchronize\_flags
+ If true, then the following maildir flags (in message filenames)
+ will be synchronized with the corresponding notmuch tags:
+
+ +--------+-----------------------------------------------+
+ | Flag | Tag |
+ +========+===============================================+
+ | D | draft |
+ +--------+-----------------------------------------------+
+ | F | flagged |
+ +--------+-----------------------------------------------+
+ | P | passed |
+ +--------+-----------------------------------------------+
+ | R | replied |
+ +--------+-----------------------------------------------+
+ | S | unread (added when 'S' flag is not present) |
+ +--------+-----------------------------------------------+
+
+ The :any:`notmuch-new(1)` command will notice flag changes in
+ filenames and update tags, while the :any:`notmuch-tag(1)` and
+ :any:`notmuch-restore(1)` commands will notice tag changes and
+ update flags in filenames.
+
+ If there have been any changes in the maildir (new messages added,
+ old ones removed or renamed, maildir flags changed, etc.), it is
+ advisable to run :any:`notmuch-new(1)` before
+ :any:`notmuch-tag(1)` or :any:`notmuch-restore(1)` commands to
+ ensure the tag changes are properly synchronized to the maildir
+ flags, as the commands expect the database and maildir to be in
+ sync.
+
+ Default: ``true``.
+
+index.decrypt
+ Policy for decrypting encrypted messages during indexing. Must be
+ one of: ``false``, ``auto``, ``nostash``, or ``true``.
+
+ When indexing an encrypted e-mail message, if this variable is set
+ to ``true``, notmuch will try to decrypt the message and index the
+ cleartext, stashing a copy of any discovered session keys for the
+ message. If ``auto``, it will try to index the cleartext if a
+ stashed session key is already known for the message (e.g. from a
+ previous copy), but will not try to access your secret keys. Use
+ ``false`` to avoid decrypting even when a stashed session key is
+ already present.
+
+ ``nostash`` is the same as ``true`` except that it will not stash
+ newly-discovered session keys in the database.
+
+ From the command line (i.e. during :any:`notmuch-new(1)`,
+ :any:`notmuch-insert(1)`, or :any:`notmuch-reindex(1)`), the user can
+ override the database's stored decryption policy with the
+ ``--decrypt=`` option.
+
+ Here is a table that summarizes the functionality of each of these
+ policies:
+
+ +------------------------+-------+------+---------+------+
+ | | false | auto | nostash | true |
+ +========================+=======+======+=========+======+
+ | Index cleartext using | | X | X | X |
+ | stashed session keys | | | | |
+ +------------------------+-------+------+---------+------+
+ | Index cleartext | | | X | X |
+ | using secret keys | | | | |
+ +------------------------+-------+------+---------+------+
+ | Stash session keys | | | | X |
+ +------------------------+-------+------+---------+------+
+ | Delete stashed session | X | | | |
+ | keys on reindex | | | | |
+ +------------------------+-------+------+---------+------+
+
+ Stashed session keys are kept in the database as properties
+ associated with the message. See ``session-key`` in
+ :any:`notmuch-properties(7)` for more details about how they can be
+ useful.
+
+ Be aware that the notmuch index is likely sufficient (and a
+ stashed session key is certainly sufficient) to reconstruct the
+ cleartext of the message itself, so please ensure that the notmuch
+ message index is adequately protected. DO NOT USE
+ ``index.decrypt=true`` or ``index.decrypt=nostash`` without
+ considering the security of your index.
+
+ Default: ``auto``.
+
+index.header.<prefix>
+ Define the query prefix <prefix>, based on a mail header. For
+ example ``index.header.List=List-Id`` will add a probabilistic
+ prefix ``List:`` that searches the ``List-Id`` field. User
+ defined prefixes must not start with 'a'...'z'; in particular
+ adding a prefix with same name as a predefined prefix is not
+ supported. See :any:`notmuch-search-terms(7)` for a list of existing
+ prefixes, and an explanation of probabilistic prefixes.
+
+built_with.<name>
+ Compile time feature <name>. Current possibilities include
+ "retry_lock" (configure option, included by default).
+ (since notmuch 0.30, "compact" and "field_processor" are
+ always included.)
+
+query.<name>
+ Expansion for named query called <name>. See
+ :any:`notmuch-search-terms(7)` for more information about named
+ queries.
+
+squery.<name>
+ Expansion for named query called <name>, using s-expression syntax. See
+ :any:`notmuch-sexp-queries(7)` for more information about s-expression
+ queries.
+
+FILES
+=====
+
+.. _config_search:
+
+CONFIGURATION
+-------------
+
+Notmuch configuration file search order:
+
+1. File specified by :option:`notmuch --config` global option; see
+ :any:`notmuch(1)`.
+
+2. File specified by :envvar:`NOTMUCH_CONFIG` environment variable.
+
+3. ``$XDG_CONFIG_HOME/notmuch/<profile>/config`` where ``<profile>``
+ is defined by :envvar:`NOTMUCH_PROFILE` environment variable if
+ set, ``$XDG_CONFIG_HOME/notmuch/default/config`` otherwise.
+
+4. ``$HOME/.notmuch-config.<profile>`` where ``<profile>`` is defined
+ by :envvar:`NOTMUCH_PROFILE` environment variable if set,
+ ``$HOME/.notmuch-config`` otherwise.
+
+.. _database:
+
+DATABASE LOCATION
+-----------------
+
+Notmuch database search order:
+
+1. Directory specified by :envvar:`NOTMUCH_DATABASE` environment variable.
+
+2. Directory specified by config key ``database.path``.
+
+3. ``$XDG_DATA_HOME/notmuch/<profile>`` where ``<profile>``
+ is defined by :envvar:`NOTMUCH_PROFILE` environment variable if
+ set, ``$XDG_DATA_HOME/notmuch/default`` otherwise.
+
+4. Directory specified by :envvar:`MAILDIR` environment variable.
+
+5. ``$HOME/mail``
+
+HOOKS
+-----
+
+Notmuch hook directory search order:
+
+1. Directory specified by ``database.hook_dir`` configuration option.