1 /* notmuch - Not much of an email library, (just index and search)
3 * Copyright © 2009 Carl Worth
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see http://www.gnu.org/licenses/ .
18 * Author: Carl Worth <cworth@cworth.org>
22 * @defgroup notmuch The notmuch API
24 * Not much of an email library, (just index and search)
35 # define NOTMUCH_BEGIN_DECLS extern "C" {
36 # define NOTMUCH_END_DECLS }
38 # define NOTMUCH_BEGIN_DECLS
39 # define NOTMUCH_END_DECLS
55 * The library version number. This must agree with the soname
56 * version in Makefile.local.
58 #define LIBNOTMUCH_MAJOR_VERSION 3
59 #define LIBNOTMUCH_MINOR_VERSION 1
60 #define LIBNOTMUCH_MICRO_VERSION 0
62 #endif /* __DOXYGEN__ */
65 * Check the version of the notmuch library being compiled against.
67 * Return true if the library being compiled against is of the
68 * specified version or above. For example:
71 * #if LIBNOTMUCH_CHECK_VERSION(3, 1, 0)
72 * (code requiring libnotmuch 3.1.0 or above)
76 * LIBNOTMUCH_CHECK_VERSION has been defined since version 3.1.0; to
77 * check for versions prior to that, use:
80 * #if !defined(NOTMUCH_CHECK_VERSION)
81 * (code requiring libnotmuch prior to 3.1.0)
85 #define LIBNOTMUCH_CHECK_VERSION (major, minor, micro) \
86 (LIBNOTMUCH_MAJOR_VERSION > (major) || \
87 (LIBNOTMUCH_MAJOR_VERSION == (major) && LIBNOTMUCH_MINOR_VERSION > (minor)) || \
88 (LIBNOTMUCH_MAJOR_VERSION == (major) && LIBNOTMUCH_MINOR_VERSION == (minor) && \
89 LIBNOTMUCH_MICRO_VERSION >= (micro)))
92 * Notmuch boolean type.
94 typedef int notmuch_bool_t;
97 * Status codes used for the return values of most functions.
99 * A zero value (NOTMUCH_STATUS_SUCCESS) indicates that the function
100 * completed without error. Any other value indicates an error.
102 typedef enum _notmuch_status {
106 NOTMUCH_STATUS_SUCCESS = 0,
110 NOTMUCH_STATUS_OUT_OF_MEMORY,
112 * An attempt was made to write to a database opened in read-only
115 NOTMUCH_STATUS_READ_ONLY_DATABASE,
117 * A Xapian exception occurred.
119 NOTMUCH_STATUS_XAPIAN_EXCEPTION,
121 * An error occurred trying to read or write to a file (this could
122 * be file not found, permission denied, etc.)
124 * @todo We don't really want to expose this lame XAPIAN_EXCEPTION
125 * value. Instead we should map to things like DATABASE_LOCKED or
128 NOTMUCH_STATUS_FILE_ERROR,
130 * A file was presented that doesn't appear to be an email
133 NOTMUCH_STATUS_FILE_NOT_EMAIL,
135 * A file contains a message ID that is identical to a message
136 * already in the database.
138 NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID,
140 * The user erroneously passed a NULL pointer to a notmuch
143 NOTMUCH_STATUS_NULL_POINTER,
145 * A tag value is too long (exceeds NOTMUCH_TAG_MAX).
147 NOTMUCH_STATUS_TAG_TOO_LONG,
149 * The notmuch_message_thaw function has been called more times
150 * than notmuch_message_freeze.
152 NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW,
154 * notmuch_database_end_atomic has been called more times than
155 * notmuch_database_begin_atomic.
157 NOTMUCH_STATUS_UNBALANCED_ATOMIC,
159 * The operation is not supported.
161 NOTMUCH_STATUS_UNSUPPORTED_OPERATION,
163 * Not an actual status value. Just a way to find out how many
164 * valid status values there are.
166 NOTMUCH_STATUS_LAST_STATUS
170 * Get a string representation of a notmuch_status_t value.
172 * The result is read-only.
175 notmuch_status_to_string (notmuch_status_t status);
177 /* Various opaque data types. For each notmuch_<foo>_t see the various
178 * notmuch_<foo> functions below. */
180 typedef struct _notmuch_database notmuch_database_t;
181 typedef struct _notmuch_query notmuch_query_t;
182 typedef struct _notmuch_threads notmuch_threads_t;
183 typedef struct _notmuch_thread notmuch_thread_t;
184 typedef struct _notmuch_messages notmuch_messages_t;
185 typedef struct _notmuch_message notmuch_message_t;
186 typedef struct _notmuch_tags notmuch_tags_t;
187 typedef struct _notmuch_directory notmuch_directory_t;
188 typedef struct _notmuch_filenames notmuch_filenames_t;
189 #endif /* __DOXYGEN__ */
192 * Create a new, empty notmuch database located at 'path'.
194 * The path should be a top-level directory to a collection of
195 * plain-text email messages (one message per file). This call will
196 * create a new ".notmuch" directory within 'path' where notmuch will
199 * After a successful call to notmuch_database_create, the returned
200 * database will be open so the caller should call
201 * notmuch_database_destroy when finished with it.
203 * The database will not yet have any data in it
204 * (notmuch_database_create itself is a very cheap function). Messages
205 * contained within 'path' can be added to the database by calling
206 * notmuch_database_add_message.
208 * In case of any failure, this function returns an error status and
209 * sets *database to NULL (after printing an error message on stderr).
213 * NOTMUCH_STATUS_SUCCESS: Successfully created the database.
215 * NOTMUCH_STATUS_NULL_POINTER: The given 'path' argument is NULL.
217 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory.
219 * NOTMUCH_STATUS_FILE_ERROR: An error occurred trying to create the
220 * database file (such as permission denied, or file not found,
221 * etc.), or the database already exists.
223 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred.
226 notmuch_database_create (const char *path, notmuch_database_t **database);
229 * Database open mode for notmuch_database_open.
233 * Open database for reading only.
235 NOTMUCH_DATABASE_MODE_READ_ONLY = 0,
237 * Open database for reading and writing.
239 NOTMUCH_DATABASE_MODE_READ_WRITE
240 } notmuch_database_mode_t;
243 * Open an existing notmuch database located at 'path'.
245 * The database should have been created at some time in the past,
246 * (not necessarily by this process), by calling
247 * notmuch_database_create with 'path'. By default the database should be
248 * opened for reading only. In order to write to the database you need to
249 * pass the NOTMUCH_DATABASE_MODE_READ_WRITE mode.
251 * An existing notmuch database can be identified by the presence of a
252 * directory named ".notmuch" below 'path'.
254 * The caller should call notmuch_database_destroy when finished with
257 * In case of any failure, this function returns an error status and
258 * sets *database to NULL (after printing an error message on stderr).
262 * NOTMUCH_STATUS_SUCCESS: Successfully opened the database.
264 * NOTMUCH_STATUS_NULL_POINTER: The given 'path' argument is NULL.
266 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory.
268 * NOTMUCH_STATUS_FILE_ERROR: An error occurred trying to open the
269 * database file (such as permission denied, or file not found,
270 * etc.), or the database version is unknown.
272 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred.
275 notmuch_database_open (const char *path,
276 notmuch_database_mode_t mode,
277 notmuch_database_t **database);
280 * Close the given notmuch database.
282 * After notmuch_database_close has been called, calls to other
283 * functions on objects derived from this database may either behave
284 * as if the database had not been closed (e.g., if the required data
285 * has been cached) or may fail with a
286 * NOTMUCH_STATUS_XAPIAN_EXCEPTION.
288 * notmuch_database_close can be called multiple times. Later calls
292 notmuch_database_close (notmuch_database_t *database);
295 * A callback invoked by notmuch_database_compact to notify the user
296 * of the progress of the compaction process.
298 typedef void (*notmuch_compact_status_cb_t)(const char *message, void *closure);
301 * Compact a notmuch database, backing up the original database to the
304 * The database will be opened with NOTMUCH_DATABASE_MODE_READ_WRITE
305 * during the compaction process to ensure no writes are made.
307 * If the optional callback function 'status_cb' is non-NULL, it will
308 * be called with diagnostic and informational messages. The argument
309 * 'closure' is passed verbatim to any callback invoked.
312 notmuch_database_compact (const char* path,
313 const char* backup_path,
314 notmuch_compact_status_cb_t status_cb,
318 * Destroy the notmuch database, closing it if necessary and freeing
319 * all associated resources.
322 notmuch_database_destroy (notmuch_database_t *database);
325 * Return the database path of the given database.
327 * The return value is a string owned by notmuch so should not be
328 * modified nor freed by the caller.
331 notmuch_database_get_path (notmuch_database_t *database);
334 * Return the database format version of the given database.
337 notmuch_database_get_version (notmuch_database_t *database);
340 * Does this database need to be upgraded before writing to it?
342 * If this function returns TRUE then no functions that modify the
343 * database (notmuch_database_add_message, notmuch_message_add_tag,
344 * notmuch_directory_set_mtime, etc.) will work unless the function
345 * notmuch_database_upgrade is called successfully first.
348 notmuch_database_needs_upgrade (notmuch_database_t *database);
351 * Upgrade the current database.
353 * After opening a database in read-write mode, the client should
354 * check if an upgrade is needed (notmuch_database_needs_upgrade) and
355 * if so, upgrade with this function before making any modifications.
357 * The optional progress_notify callback can be used by the caller to
358 * provide progress indication to the user. If non-NULL it will be
359 * called periodically with 'progress' as a floating-point value in
360 * the range of [0.0 .. 1.0] indicating the progress made so far in
361 * the upgrade process. The argument 'closure' is passed verbatim to
362 * any callback invoked.
365 notmuch_database_upgrade (notmuch_database_t *database,
366 void (*progress_notify) (void *closure,
371 * Begin an atomic database operation.
373 * Any modifications performed between a successful begin and a
374 * notmuch_database_end_atomic will be applied to the database
375 * atomically. Note that, unlike a typical database transaction, this
376 * only ensures atomicity, not durability; neither begin nor end
377 * necessarily flush modifications to disk.
379 * Atomic sections may be nested. begin_atomic and end_atomic must
380 * always be called in pairs.
384 * NOTMUCH_STATUS_SUCCESS: Successfully entered atomic section.
386 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred;
387 * atomic section not entered.
390 notmuch_database_begin_atomic (notmuch_database_t *notmuch);
393 * Indicate the end of an atomic database operation.
397 * NOTMUCH_STATUS_SUCCESS: Successfully completed atomic section.
399 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred;
400 * atomic section not ended.
402 * NOTMUCH_STATUS_UNBALANCED_ATOMIC: The database is not currently in
406 notmuch_database_end_atomic (notmuch_database_t *notmuch);
409 * Retrieve a directory object from the database for 'path'.
411 * Here, 'path' should be a path relative to the path of 'database'
412 * (see notmuch_database_get_path), or else should be an absolute path
413 * with initial components that match the path of 'database'.
415 * If this directory object does not exist in the database, this
416 * returns NOTMUCH_STATUS_SUCCESS and sets *directory to NULL.
418 * Otherwise the returned directory object is owned by the database
419 * and as such, will only be valid until notmuch_database_destroy is
424 * NOTMUCH_STATUS_SUCCESS: Successfully retrieved directory.
426 * NOTMUCH_STATUS_NULL_POINTER: The given 'directory' argument is NULL.
428 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred;
429 * directory not retrieved.
432 notmuch_database_get_directory (notmuch_database_t *database,
434 notmuch_directory_t **directory);
437 * Add a new message to the given notmuch database or associate an
438 * additional filename with an existing message.
440 * Here, 'filename' should be a path relative to the path of
441 * 'database' (see notmuch_database_get_path), or else should be an
442 * absolute filename with initial components that match the path of
445 * The file should be a single mail message (not a multi-message mbox)
446 * that is expected to remain at its current location, (since the
447 * notmuch database will reference the filename, and will not copy the
448 * entire contents of the file.
450 * If another message with the same message ID already exists in the
451 * database, rather than creating a new message, this adds 'filename'
452 * to the list of the filenames for the existing message.
454 * If 'message' is not NULL, then, on successful return
455 * (NOTMUCH_STATUS_SUCCESS or NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID) '*message'
456 * will be initialized to a message object that can be used for things
457 * such as adding tags to the just-added message. The user should call
458 * notmuch_message_destroy when done with the message. On any failure
459 * '*message' will be set to NULL.
463 * NOTMUCH_STATUS_SUCCESS: Message successfully added to database.
465 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred,
468 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: Message has the same message
469 * ID as another message already in the database. The new
470 * filename was successfully added to the message in the database
471 * (if not already present) and the existing message is returned.
473 * NOTMUCH_STATUS_FILE_ERROR: an error occurred trying to open the
474 * file, (such as permission denied, or file not found,
475 * etc.). Nothing added to the database.
477 * NOTMUCH_STATUS_FILE_NOT_EMAIL: the contents of filename don't look
478 * like an email message. Nothing added to the database.
480 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
481 * mode so no message can be added.
484 notmuch_database_add_message (notmuch_database_t *database,
485 const char *filename,
486 notmuch_message_t **message);
489 * Remove a message filename from the given notmuch database. If the
490 * message has no more filenames, remove the message.
492 * If the same message (as determined by the message ID) is still
493 * available via other filenames, then the message will persist in the
494 * database for those filenames. When the last filename is removed for
495 * a particular message, the database content for that message will be
500 * NOTMUCH_STATUS_SUCCESS: The last filename was removed and the
501 * message was removed from the database.
503 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred,
504 * message not removed.
506 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: This filename was removed but
507 * the message persists in the database with at least one other
510 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
511 * mode so no message can be removed.
514 notmuch_database_remove_message (notmuch_database_t *database,
515 const char *filename);
518 * Find a message with the given message_id.
520 * If a message with the given message_id is found then, on successful return
521 * (NOTMUCH_STATUS_SUCCESS) '*message' will be initialized to a message
522 * object. The caller should call notmuch_message_destroy when done with the
525 * On any failure or when the message is not found, this function initializes
526 * '*message' to NULL. This means, when NOTMUCH_STATUS_SUCCESS is returned, the
527 * caller is supposed to check '*message' for NULL to find out whether the
528 * message with the given message_id was found.
532 * NOTMUCH_STATUS_SUCCESS: Successful return, check '*message'.
534 * NOTMUCH_STATUS_NULL_POINTER: The given 'message' argument is NULL
536 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory, creating message object
538 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred
541 notmuch_database_find_message (notmuch_database_t *database,
542 const char *message_id,
543 notmuch_message_t **message);
546 * Find a message with the given filename.
548 * If the database contains a message with the given filename then, on
549 * successful return (NOTMUCH_STATUS_SUCCESS) '*message' will be initialized to
550 * a message object. The caller should call notmuch_message_destroy when done
553 * On any failure or when the message is not found, this function initializes
554 * '*message' to NULL. This means, when NOTMUCH_STATUS_SUCCESS is returned, the
555 * caller is supposed to check '*message' for NULL to find out whether the
556 * message with the given filename is found.
560 * NOTMUCH_STATUS_SUCCESS: Successful return, check '*message'
562 * NOTMUCH_STATUS_NULL_POINTER: The given 'message' argument is NULL
564 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory, creating the message object
566 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred
569 notmuch_database_find_message_by_filename (notmuch_database_t *notmuch,
570 const char *filename,
571 notmuch_message_t **message);
574 * Return a list of all tags found in the database.
576 * This function creates a list of all tags found in the database. The
577 * resulting list contains all tags from all messages found in the database.
579 * On error this function returns NULL.
582 notmuch_database_get_all_tags (notmuch_database_t *db);
585 * Create a new query for 'database'.
587 * Here, 'database' should be an open database, (see
588 * notmuch_database_open and notmuch_database_create).
590 * For the query string, we'll document the syntax here more
591 * completely in the future, but it's likely to be a specialized
592 * version of the general Xapian query syntax:
594 * http://xapian.org/docs/queryparser.html
596 * As a special case, passing either a length-zero string, (that is ""),
597 * or a string consisting of a single asterisk (that is "*"), will
598 * result in a query that returns all messages in the database.
600 * See notmuch_query_set_sort for controlling the order of results.
601 * See notmuch_query_search_messages and notmuch_query_search_threads
602 * to actually execute the query.
604 * User should call notmuch_query_destroy when finished with this
607 * Will return NULL if insufficient memory is available.
610 notmuch_query_create (notmuch_database_t *database,
611 const char *query_string);
614 * Sort values for notmuch_query_set_sort.
620 NOTMUCH_SORT_OLDEST_FIRST,
624 NOTMUCH_SORT_NEWEST_FIRST,
626 * Sort by message-id.
628 NOTMUCH_SORT_MESSAGE_ID,
632 NOTMUCH_SORT_UNSORTED
636 * Return the query_string of this query. See notmuch_query_create.
639 notmuch_query_get_query_string (notmuch_query_t *query);
642 * Exclude values for notmuch_query_set_omit_excluded. The strange
643 * order is to maintain backward compatibility: the old FALSE/TRUE
644 * options correspond to the new
645 * NOTMUCH_EXCLUDE_FLAG/NOTMUCH_EXCLUDE_TRUE options.
648 NOTMUCH_EXCLUDE_FLAG,
649 NOTMUCH_EXCLUDE_TRUE,
650 NOTMUCH_EXCLUDE_FALSE,
655 * Specify whether to omit excluded results or simply flag them. By
656 * default, this is set to TRUE.
658 * If set to TRUE or ALL, notmuch_query_search_messages will omit excluded
659 * messages from the results, and notmuch_query_search_threads will omit
660 * threads that match only in excluded messages. If set to TRUE,
661 * notmuch_query_search_threads will include all messages in threads that
662 * match in at least one non-excluded message. Otherwise, if set to ALL,
663 * notmuch_query_search_threads will omit excluded messages from all threads.
665 * If set to FALSE or FLAG then both notmuch_query_search_messages and
666 * notmuch_query_search_threads will return all matching
667 * messages/threads regardless of exclude status. If set to FLAG then
668 * the exclude flag will be set for any excluded message that is
669 * returned by notmuch_query_search_messages, and the thread counts
670 * for threads returned by notmuch_query_search_threads will be the
671 * number of non-excluded messages/matches. Otherwise, if set to
672 * FALSE, then the exclude status is completely ignored.
674 * The performance difference when calling
675 * notmuch_query_search_messages should be relatively small (and both
676 * should be very fast). However, in some cases,
677 * notmuch_query_search_threads is very much faster when omitting
678 * excluded messages as it does not need to construct the threads that
679 * only match in excluded messages.
682 notmuch_query_set_omit_excluded (notmuch_query_t *query,
683 notmuch_exclude_t omit_excluded);
686 * Specify the sorting desired for this query.
689 notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort);
692 * Return the sort specified for this query. See
693 * notmuch_query_set_sort.
696 notmuch_query_get_sort (notmuch_query_t *query);
699 * Add a tag that will be excluded from the query results by default.
700 * This exclusion will be overridden if this tag appears explicitly in
704 notmuch_query_add_tag_exclude (notmuch_query_t *query, const char *tag);
707 * Execute a query for threads, returning a notmuch_threads_t object
708 * which can be used to iterate over the results. The returned threads
709 * object is owned by the query and as such, will only be valid until
710 * notmuch_query_destroy.
712 * Typical usage might be:
714 * notmuch_query_t *query;
715 * notmuch_threads_t *threads;
716 * notmuch_thread_t *thread;
718 * query = notmuch_query_create (database, query_string);
720 * for (threads = notmuch_query_search_threads (query);
721 * notmuch_threads_valid (threads);
722 * notmuch_threads_move_to_next (threads))
724 * thread = notmuch_threads_get (threads);
726 * notmuch_thread_destroy (thread);
729 * notmuch_query_destroy (query);
731 * Note: If you are finished with a thread before its containing
732 * query, you can call notmuch_thread_destroy to clean up some memory
733 * sooner (as in the above example). Otherwise, if your thread objects
734 * are long-lived, then you don't need to call notmuch_thread_destroy
735 * and all the memory will still be reclaimed when the query is
738 * Note that there's no explicit destructor needed for the
739 * notmuch_threads_t object. (For consistency, we do provide a
740 * notmuch_threads_destroy function, but there's no good reason
741 * to call it if the query is about to be destroyed).
743 * If a Xapian exception occurs this function will return NULL.
746 notmuch_query_search_threads (notmuch_query_t *query);
749 * Execute a query for messages, returning a notmuch_messages_t object
750 * which can be used to iterate over the results. The returned
751 * messages object is owned by the query and as such, will only be
752 * valid until notmuch_query_destroy.
754 * Typical usage might be:
756 * notmuch_query_t *query;
757 * notmuch_messages_t *messages;
758 * notmuch_message_t *message;
760 * query = notmuch_query_create (database, query_string);
762 * for (messages = notmuch_query_search_messages (query);
763 * notmuch_messages_valid (messages);
764 * notmuch_messages_move_to_next (messages))
766 * message = notmuch_messages_get (messages);
768 * notmuch_message_destroy (message);
771 * notmuch_query_destroy (query);
773 * Note: If you are finished with a message before its containing
774 * query, you can call notmuch_message_destroy to clean up some memory
775 * sooner (as in the above example). Otherwise, if your message
776 * objects are long-lived, then you don't need to call
777 * notmuch_message_destroy and all the memory will still be reclaimed
778 * when the query is destroyed.
780 * Note that there's no explicit destructor needed for the
781 * notmuch_messages_t object. (For consistency, we do provide a
782 * notmuch_messages_destroy function, but there's no good
783 * reason to call it if the query is about to be destroyed).
785 * If a Xapian exception occurs this function will return NULL.
788 notmuch_query_search_messages (notmuch_query_t *query);
791 * Destroy a notmuch_query_t along with any associated resources.
793 * This will in turn destroy any notmuch_threads_t and
794 * notmuch_messages_t objects generated by this query, (and in
795 * turn any notmuch_thread_t and notmuch_message_t objects generated
796 * from those results, etc.), if such objects haven't already been
800 notmuch_query_destroy (notmuch_query_t *query);
803 * Is the given 'threads' iterator pointing at a valid thread.
805 * When this function returns TRUE, notmuch_threads_get will return a
806 * valid object. Whereas when this function returns FALSE,
807 * notmuch_threads_get will return NULL.
809 * If passed a NULL pointer, this function returns FALSE
811 * See the documentation of notmuch_query_search_threads for example
812 * code showing how to iterate over a notmuch_threads_t object.
815 notmuch_threads_valid (notmuch_threads_t *threads);
818 * Get the current thread from 'threads' as a notmuch_thread_t.
820 * Note: The returned thread belongs to 'threads' and has a lifetime
821 * identical to it (and the query to which it belongs).
823 * See the documentation of notmuch_query_search_threads for example
824 * code showing how to iterate over a notmuch_threads_t object.
826 * If an out-of-memory situation occurs, this function will return
830 notmuch_threads_get (notmuch_threads_t *threads);
833 * Move the 'threads' iterator to the next thread.
835 * If 'threads' is already pointing at the last thread then the
836 * iterator will be moved to a point just beyond that last thread,
837 * (where notmuch_threads_valid will return FALSE and
838 * notmuch_threads_get will return NULL).
840 * See the documentation of notmuch_query_search_threads for example
841 * code showing how to iterate over a notmuch_threads_t object.
844 notmuch_threads_move_to_next (notmuch_threads_t *threads);
847 * Destroy a notmuch_threads_t object.
849 * It's not strictly necessary to call this function. All memory from
850 * the notmuch_threads_t object will be reclaimed when the
851 * containing query object is destroyed.
854 notmuch_threads_destroy (notmuch_threads_t *threads);
857 * Return an estimate of the number of messages matching a search.
859 * This function performs a search and returns Xapian's best
860 * guess as to number of matching messages.
862 * If a Xapian exception occurs, this function may return 0 (after
863 * printing a message).
866 notmuch_query_count_messages (notmuch_query_t *query);
869 * Return the number of threads matching a search.
871 * This function performs a search and returns the number of unique thread IDs
872 * in the matching messages. This is the same as number of threads matching a
875 * Note that this is a significantly heavier operation than
876 * notmuch_query_count_messages().
878 * If an error occurs, this function may return 0.
881 notmuch_query_count_threads (notmuch_query_t *query);
884 * Get the thread ID of 'thread'.
886 * The returned string belongs to 'thread' and as such, should not be
887 * modified by the caller and will only be valid for as long as the
888 * thread is valid, (which is until notmuch_thread_destroy or until
889 * the query from which it derived is destroyed).
892 notmuch_thread_get_thread_id (notmuch_thread_t *thread);
895 * Get the total number of messages in 'thread'.
897 * This count consists of all messages in the database belonging to
898 * this thread. Contrast with notmuch_thread_get_matched_messages() .
901 notmuch_thread_get_total_messages (notmuch_thread_t *thread);
904 * Get a notmuch_messages_t iterator for the top-level messages in
905 * 'thread' in oldest-first order.
907 * This iterator will not necessarily iterate over all of the messages
908 * in the thread. It will only iterate over the messages in the thread
909 * which are not replies to other messages in the thread.
911 * The returned list will be destroyed when the thread is destroyed.
914 notmuch_thread_get_toplevel_messages (notmuch_thread_t *thread);
917 * Get a notmuch_thread_t iterator for all messages in 'thread' in
918 * oldest-first order.
920 * The returned list will be destroyed when the thread is destroyed.
923 notmuch_thread_get_messages (notmuch_thread_t *thread);
926 * Get the number of messages in 'thread' that matched the search.
928 * This count includes only the messages in this thread that were
929 * matched by the search from which the thread was created and were
930 * not excluded by any exclude tags passed in with the query (see
931 * notmuch_query_add_tag_exclude). Contrast with
932 * notmuch_thread_get_total_messages() .
935 notmuch_thread_get_matched_messages (notmuch_thread_t *thread);
938 * Get the authors of 'thread' as a UTF-8 string.
940 * The returned string is a comma-separated list of the names of the
941 * authors of mail messages in the query results that belong to this
944 * The returned string belongs to 'thread' and as such, should not be
945 * modified by the caller and will only be valid for as long as the
946 * thread is valid, (which is until notmuch_thread_destroy or until
947 * the query from which it derived is destroyed).
950 notmuch_thread_get_authors (notmuch_thread_t *thread);
953 * Get the subject of 'thread' as a UTF-8 string.
955 * The subject is taken from the first message (according to the query
956 * order---see notmuch_query_set_sort) in the query results that
957 * belongs to this thread.
959 * The returned string belongs to 'thread' and as such, should not be
960 * modified by the caller and will only be valid for as long as the
961 * thread is valid, (which is until notmuch_thread_destroy or until
962 * the query from which it derived is destroyed).
965 notmuch_thread_get_subject (notmuch_thread_t *thread);
968 * Get the date of the oldest message in 'thread' as a time_t value.
971 notmuch_thread_get_oldest_date (notmuch_thread_t *thread);
974 * Get the date of the newest message in 'thread' as a time_t value.
977 notmuch_thread_get_newest_date (notmuch_thread_t *thread);
980 * Get the tags for 'thread', returning a notmuch_tags_t object which
981 * can be used to iterate over all tags.
983 * Note: In the Notmuch database, tags are stored on individual
984 * messages, not on threads. So the tags returned here will be all
985 * tags of the messages which matched the search and which belong to
988 * The tags object is owned by the thread and as such, will only be
989 * valid for as long as the thread is valid, (for example, until
990 * notmuch_thread_destroy or until the query from which it derived is
993 * Typical usage might be:
995 * notmuch_thread_t *thread;
996 * notmuch_tags_t *tags;
999 * thread = notmuch_threads_get (threads);
1001 * for (tags = notmuch_thread_get_tags (thread);
1002 * notmuch_tags_valid (tags);
1003 * notmuch_tags_move_to_next (tags))
1005 * tag = notmuch_tags_get (tags);
1009 * notmuch_thread_destroy (thread);
1011 * Note that there's no explicit destructor needed for the
1012 * notmuch_tags_t object. (For consistency, we do provide a
1013 * notmuch_tags_destroy function, but there's no good reason to call
1014 * it if the message is about to be destroyed).
1017 notmuch_thread_get_tags (notmuch_thread_t *thread);
1020 * Destroy a notmuch_thread_t object.
1023 notmuch_thread_destroy (notmuch_thread_t *thread);
1026 * Is the given 'messages' iterator pointing at a valid message.
1028 * When this function returns TRUE, notmuch_messages_get will return a
1029 * valid object. Whereas when this function returns FALSE,
1030 * notmuch_messages_get will return NULL.
1032 * See the documentation of notmuch_query_search_messages for example
1033 * code showing how to iterate over a notmuch_messages_t object.
1036 notmuch_messages_valid (notmuch_messages_t *messages);
1039 * Get the current message from 'messages' as a notmuch_message_t.
1041 * Note: The returned message belongs to 'messages' and has a lifetime
1042 * identical to it (and the query to which it belongs).
1044 * See the documentation of notmuch_query_search_messages for example
1045 * code showing how to iterate over a notmuch_messages_t object.
1047 * If an out-of-memory situation occurs, this function will return
1051 notmuch_messages_get (notmuch_messages_t *messages);
1054 * Move the 'messages' iterator to the next message.
1056 * If 'messages' is already pointing at the last message then the
1057 * iterator will be moved to a point just beyond that last message,
1058 * (where notmuch_messages_valid will return FALSE and
1059 * notmuch_messages_get will return NULL).
1061 * See the documentation of notmuch_query_search_messages for example
1062 * code showing how to iterate over a notmuch_messages_t object.
1065 notmuch_messages_move_to_next (notmuch_messages_t *messages);
1068 * Destroy a notmuch_messages_t object.
1070 * It's not strictly necessary to call this function. All memory from
1071 * the notmuch_messages_t object will be reclaimed when the containing
1072 * query object is destroyed.
1075 notmuch_messages_destroy (notmuch_messages_t *messages);
1078 * Return a list of tags from all messages.
1080 * The resulting list is guaranteed not to contain duplicated tags.
1082 * WARNING: You can no longer iterate over messages after calling this
1083 * function, because the iterator will point at the end of the list.
1084 * We do not have a function to reset the iterator yet and the only
1085 * way how you can iterate over the list again is to recreate the
1088 * The function returns NULL on error.
1091 notmuch_messages_collect_tags (notmuch_messages_t *messages);
1094 * Get the message ID of 'message'.
1096 * The returned string belongs to 'message' and as such, should not be
1097 * modified by the caller and will only be valid for as long as the
1098 * message is valid, (which is until the query from which it derived
1101 * This function will not return NULL since Notmuch ensures that every
1102 * message has a unique message ID, (Notmuch will generate an ID for a
1103 * message if the original file does not contain one).
1106 notmuch_message_get_message_id (notmuch_message_t *message);
1109 * Get the thread ID of 'message'.
1111 * The returned string belongs to 'message' and as such, should not be
1112 * modified by the caller and will only be valid for as long as the
1113 * message is valid, (for example, until the user calls
1114 * notmuch_message_destroy on 'message' or until a query from which it
1115 * derived is destroyed).
1117 * This function will not return NULL since Notmuch ensures that every
1118 * message belongs to a single thread.
1121 notmuch_message_get_thread_id (notmuch_message_t *message);
1124 * Get a notmuch_messages_t iterator for all of the replies to
1127 * Note: This call only makes sense if 'message' was ultimately
1128 * obtained from a notmuch_thread_t object, (such as by coming
1129 * directly from the result of calling notmuch_thread_get_
1130 * toplevel_messages or by any number of subsequent
1131 * calls to notmuch_message_get_replies).
1133 * If 'message' was obtained through some non-thread means, (such as
1134 * by a call to notmuch_query_search_messages), then this function
1137 * If there are no replies to 'message', this function will return
1138 * NULL. (Note that notmuch_messages_valid will accept that NULL
1139 * value as legitimate, and simply return FALSE for it.)
1141 notmuch_messages_t *
1142 notmuch_message_get_replies (notmuch_message_t *message);
1145 * Get a filename for the email corresponding to 'message'.
1147 * The returned filename is an absolute filename, (the initial
1148 * component will match notmuch_database_get_path() ).
1150 * The returned string belongs to the message so should not be
1151 * modified or freed by the caller (nor should it be referenced after
1152 * the message is destroyed).
1154 * Note: If this message corresponds to multiple files in the mail
1155 * store, (that is, multiple files contain identical message IDs),
1156 * this function will arbitrarily return a single one of those
1157 * filenames. See notmuch_message_get_filenames for returning the
1158 * complete list of filenames.
1161 notmuch_message_get_filename (notmuch_message_t *message);
1164 * Get all filenames for the email corresponding to 'message'.
1166 * Returns a notmuch_filenames_t iterator listing all the filenames
1167 * associated with 'message'. These files may not have identical
1168 * content, but each will have the identical Message-ID.
1170 * Each filename in the iterator is an absolute filename, (the initial
1171 * component will match notmuch_database_get_path() ).
1173 notmuch_filenames_t *
1174 notmuch_message_get_filenames (notmuch_message_t *message);
1179 typedef enum _notmuch_message_flag {
1180 NOTMUCH_MESSAGE_FLAG_MATCH,
1181 NOTMUCH_MESSAGE_FLAG_EXCLUDED
1182 } notmuch_message_flag_t;
1185 * Get a value of a flag for the email corresponding to 'message'.
1188 notmuch_message_get_flag (notmuch_message_t *message,
1189 notmuch_message_flag_t flag);
1192 * Set a value of a flag for the email corresponding to 'message'.
1195 notmuch_message_set_flag (notmuch_message_t *message,
1196 notmuch_message_flag_t flag, notmuch_bool_t value);
1199 * Get the date of 'message' as a time_t value.
1201 * For the original textual representation of the Date header from the
1202 * message call notmuch_message_get_header() with a header value of
1206 notmuch_message_get_date (notmuch_message_t *message);
1209 * Get the value of the specified header from 'message' as a UTF-8 string.
1211 * Common headers are stored in the database when the message is
1212 * indexed and will be returned from the database. Other headers will
1213 * be read from the actual message file.
1215 * The header name is case insensitive.
1217 * The returned string belongs to the message so should not be
1218 * modified or freed by the caller (nor should it be referenced after
1219 * the message is destroyed).
1221 * Returns an empty string ("") if the message does not contain a
1222 * header line matching 'header'. Returns NULL if any error occurs.
1225 notmuch_message_get_header (notmuch_message_t *message, const char *header);
1228 * Get the tags for 'message', returning a notmuch_tags_t object which
1229 * can be used to iterate over all tags.
1231 * The tags object is owned by the message and as such, will only be
1232 * valid for as long as the message is valid, (which is until the
1233 * query from which it derived is destroyed).
1235 * Typical usage might be:
1237 * notmuch_message_t *message;
1238 * notmuch_tags_t *tags;
1241 * message = notmuch_database_find_message (database, message_id);
1243 * for (tags = notmuch_message_get_tags (message);
1244 * notmuch_tags_valid (tags);
1245 * notmuch_tags_move_to_next (tags))
1247 * tag = notmuch_tags_get (tags);
1251 * notmuch_message_destroy (message);
1253 * Note that there's no explicit destructor needed for the
1254 * notmuch_tags_t object. (For consistency, we do provide a
1255 * notmuch_tags_destroy function, but there's no good reason to call
1256 * it if the message is about to be destroyed).
1259 notmuch_message_get_tags (notmuch_message_t *message);
1262 * The longest possible tag value.
1264 #define NOTMUCH_TAG_MAX 200
1267 * Add a tag to the given message.
1271 * NOTMUCH_STATUS_SUCCESS: Tag successfully added to message
1273 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
1275 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
1276 * (exceeds NOTMUCH_TAG_MAX)
1278 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1279 * mode so message cannot be modified.
1282 notmuch_message_add_tag (notmuch_message_t *message, const char *tag);
1285 * Remove a tag from the given message.
1289 * NOTMUCH_STATUS_SUCCESS: Tag successfully removed from message
1291 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
1293 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
1294 * (exceeds NOTMUCH_TAG_MAX)
1296 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1297 * mode so message cannot be modified.
1300 notmuch_message_remove_tag (notmuch_message_t *message, const char *tag);
1303 * Remove all tags from the given message.
1305 * See notmuch_message_freeze for an example showing how to safely
1306 * replace tag values.
1308 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1309 * mode so message cannot be modified.
1312 notmuch_message_remove_all_tags (notmuch_message_t *message);
1315 * Add/remove tags according to maildir flags in the message filename(s).
1317 * This function examines the filenames of 'message' for maildir
1318 * flags, and adds or removes tags on 'message' as follows when these
1319 * flags are present:
1321 * Flag Action if present
1322 * ---- -----------------
1323 * 'D' Adds the "draft" tag to the message
1324 * 'F' Adds the "flagged" tag to the message
1325 * 'P' Adds the "passed" tag to the message
1326 * 'R' Adds the "replied" tag to the message
1327 * 'S' Removes the "unread" tag from the message
1329 * For each flag that is not present, the opposite action (add/remove)
1330 * is performed for the corresponding tags.
1332 * Flags are identified as trailing components of the filename after a
1333 * sequence of ":2,".
1335 * If there are multiple filenames associated with this message, the
1336 * flag is considered present if it appears in one or more
1337 * filenames. (That is, the flags from the multiple filenames are
1338 * combined with the logical OR operator.)
1340 * A client can ensure that notmuch database tags remain synchronized
1341 * with maildir flags by calling this function after each call to
1342 * notmuch_database_add_message. See also
1343 * notmuch_message_tags_to_maildir_flags for synchronizing tag changes
1344 * back to maildir flags.
1347 notmuch_message_maildir_flags_to_tags (notmuch_message_t *message);
1350 * Rename message filename(s) to encode tags as maildir flags.
1352 * Specifically, for each filename corresponding to this message:
1354 * If the filename is not in a maildir directory, do nothing. (A
1355 * maildir directory is determined as a directory named "new" or
1356 * "cur".) Similarly, if the filename has invalid maildir info,
1357 * (repeated or outof-ASCII-order flag characters after ":2,"), then
1360 * If the filename is in a maildir directory, rename the file so that
1361 * its filename ends with the sequence ":2," followed by zero or more
1362 * of the following single-character flags (in ASCII order):
1364 * 'D' iff the message has the "draft" tag
1365 * 'F' iff the message has the "flagged" tag
1366 * 'P' iff the message has the "passed" tag
1367 * 'R' iff the message has the "replied" tag
1368 * 'S' iff the message does not have the "unread" tag
1370 * Any existing flags unmentioned in the list above will be preserved
1373 * Also, if this filename is in a directory named "new", rename it to
1374 * be within the neighboring directory named "cur".
1376 * A client can ensure that maildir filename flags remain synchronized
1377 * with notmuch database tags by calling this function after changing
1378 * tags, (after calls to notmuch_message_add_tag,
1379 * notmuch_message_remove_tag, or notmuch_message_freeze/
1380 * notmuch_message_thaw). See also notmuch_message_maildir_flags_to_tags
1381 * for synchronizing maildir flag changes back to tags.
1384 notmuch_message_tags_to_maildir_flags (notmuch_message_t *message);
1387 * Freeze the current state of 'message' within the database.
1389 * This means that changes to the message state, (via
1390 * notmuch_message_add_tag, notmuch_message_remove_tag, and
1391 * notmuch_message_remove_all_tags), will not be committed to the
1392 * database until the message is thawed with notmuch_message_thaw.
1394 * Multiple calls to freeze/thaw are valid and these calls will
1395 * "stack". That is there must be as many calls to thaw as to freeze
1396 * before a message is actually thawed.
1398 * The ability to do freeze/thaw allows for safe transactions to
1399 * change tag values. For example, explicitly setting a message to
1400 * have a given set of tags might look like this:
1402 * notmuch_message_freeze (message);
1404 * notmuch_message_remove_all_tags (message);
1406 * for (i = 0; i < NUM_TAGS; i++)
1407 * notmuch_message_add_tag (message, tags[i]);
1409 * notmuch_message_thaw (message);
1411 * With freeze/thaw used like this, the message in the database is
1412 * guaranteed to have either the full set of original tag values, or
1413 * the full set of new tag values, but nothing in between.
1415 * Imagine the example above without freeze/thaw and the operation
1416 * somehow getting interrupted. This could result in the message being
1417 * left with no tags if the interruption happened after
1418 * notmuch_message_remove_all_tags but before notmuch_message_add_tag.
1422 * NOTMUCH_STATUS_SUCCESS: Message successfully frozen.
1424 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1425 * mode so message cannot be modified.
1428 notmuch_message_freeze (notmuch_message_t *message);
1431 * Thaw the current 'message', synchronizing any changes that may have
1432 * occurred while 'message' was frozen into the notmuch database.
1434 * See notmuch_message_freeze for an example of how to use this
1435 * function to safely provide tag changes.
1437 * Multiple calls to freeze/thaw are valid and these calls with
1438 * "stack". That is there must be as many calls to thaw as to freeze
1439 * before a message is actually thawed.
1443 * NOTMUCH_STATUS_SUCCESS: Message successfully thawed, (or at least
1444 * its frozen count has successfully been reduced by 1).
1446 * NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW: An attempt was made to thaw
1447 * an unfrozen message. That is, there have been an unbalanced
1448 * number of calls to notmuch_message_freeze and
1449 * notmuch_message_thaw.
1452 notmuch_message_thaw (notmuch_message_t *message);
1455 * Destroy a notmuch_message_t object.
1457 * It can be useful to call this function in the case of a single
1458 * query object with many messages in the result, (such as iterating
1459 * over the entire database). Otherwise, it's fine to never call this
1460 * function and there will still be no memory leaks. (The memory from
1461 * the messages get reclaimed when the containing query is destroyed.)
1464 notmuch_message_destroy (notmuch_message_t *message);
1467 * Is the given 'tags' iterator pointing at a valid tag.
1469 * When this function returns TRUE, notmuch_tags_get will return a
1470 * valid string. Whereas when this function returns FALSE,
1471 * notmuch_tags_get will return NULL.
1473 * See the documentation of notmuch_message_get_tags for example code
1474 * showing how to iterate over a notmuch_tags_t object.
1477 notmuch_tags_valid (notmuch_tags_t *tags);
1480 * Get the current tag from 'tags' as a string.
1482 * Note: The returned string belongs to 'tags' and has a lifetime
1483 * identical to it (and the query to which it ultimately belongs).
1485 * See the documentation of notmuch_message_get_tags for example code
1486 * showing how to iterate over a notmuch_tags_t object.
1489 notmuch_tags_get (notmuch_tags_t *tags);
1492 * Move the 'tags' iterator to the next tag.
1494 * If 'tags' is already pointing at the last tag then the iterator
1495 * will be moved to a point just beyond that last tag, (where
1496 * notmuch_tags_valid will return FALSE and notmuch_tags_get will
1499 * See the documentation of notmuch_message_get_tags for example code
1500 * showing how to iterate over a notmuch_tags_t object.
1503 notmuch_tags_move_to_next (notmuch_tags_t *tags);
1506 * Destroy a notmuch_tags_t object.
1508 * It's not strictly necessary to call this function. All memory from
1509 * the notmuch_tags_t object will be reclaimed when the containing
1510 * message or query objects are destroyed.
1513 notmuch_tags_destroy (notmuch_tags_t *tags);
1516 * Store an mtime within the database for 'directory'.
1518 * The 'directory' should be an object retrieved from the database
1519 * with notmuch_database_get_directory for a particular path.
1521 * The intention is for the caller to use the mtime to allow efficient
1522 * identification of new messages to be added to the database. The
1523 * recommended usage is as follows:
1525 * o Read the mtime of a directory from the filesystem
1527 * o Call add_message for all mail files in the directory
1529 * o Call notmuch_directory_set_mtime with the mtime read from the
1532 * Then, when wanting to check for updates to the directory in the
1533 * future, the client can call notmuch_directory_get_mtime and know
1534 * that it only needs to add files if the mtime of the directory and
1535 * files are newer than the stored timestamp.
1537 * Note: The notmuch_directory_get_mtime function does not allow the
1538 * caller to distinguish a timestamp of 0 from a non-existent
1539 * timestamp. So don't store a timestamp of 0 unless you are
1540 * comfortable with that.
1544 * NOTMUCH_STATUS_SUCCESS: mtime successfully stored in database.
1546 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception
1547 * occurred, mtime not stored.
1549 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1550 * mode so directory mtime cannot be modified.
1553 notmuch_directory_set_mtime (notmuch_directory_t *directory,
1557 * Get the mtime of a directory, (as previously stored with
1558 * notmuch_directory_set_mtime).
1560 * Returns 0 if no mtime has previously been stored for this
1564 notmuch_directory_get_mtime (notmuch_directory_t *directory);
1567 * Get a notmuch_filenames_t iterator listing all the filenames of
1568 * messages in the database within the given directory.
1570 * The returned filenames will be the basename-entries only (not
1573 notmuch_filenames_t *
1574 notmuch_directory_get_child_files (notmuch_directory_t *directory);
1577 * Get a notmuch_filenams_t iterator listing all the filenames of
1578 * sub-directories in the database within the given directory.
1580 * The returned filenames will be the basename-entries only (not
1583 notmuch_filenames_t *
1584 notmuch_directory_get_child_directories (notmuch_directory_t *directory);
1587 * Destroy a notmuch_directory_t object.
1590 notmuch_directory_destroy (notmuch_directory_t *directory);
1593 * Is the given 'filenames' iterator pointing at a valid filename.
1595 * When this function returns TRUE, notmuch_filenames_get will return
1596 * a valid string. Whereas when this function returns FALSE,
1597 * notmuch_filenames_get will return NULL.
1599 * It is acceptable to pass NULL for 'filenames', in which case this
1600 * function will always return FALSE.
1603 notmuch_filenames_valid (notmuch_filenames_t *filenames);
1606 * Get the current filename from 'filenames' as a string.
1608 * Note: The returned string belongs to 'filenames' and has a lifetime
1609 * identical to it (and the directory to which it ultimately belongs).
1611 * It is acceptable to pass NULL for 'filenames', in which case this
1612 * function will always return NULL.
1615 notmuch_filenames_get (notmuch_filenames_t *filenames);
1618 * Move the 'filenames' iterator to the next filename.
1620 * If 'filenames' is already pointing at the last filename then the
1621 * iterator will be moved to a point just beyond that last filename,
1622 * (where notmuch_filenames_valid will return FALSE and
1623 * notmuch_filenames_get will return NULL).
1625 * It is acceptable to pass NULL for 'filenames', in which case this
1626 * function will do nothing.
1629 notmuch_filenames_move_to_next (notmuch_filenames_t *filenames);
1632 * Destroy a notmuch_filenames_t object.
1634 * It's not strictly necessary to call this function. All memory from
1635 * the notmuch_filenames_t object will be reclaimed when the
1636 * containing directory object is destroyed.
1638 * It is acceptable to pass NULL for 'filenames', in which case this
1639 * function will do nothing.
1642 notmuch_filenames_destroy (notmuch_filenames_t *filenames);