1TCHDB(3) Tokyo Cabinet TCHDB(3)
2
6 tchdb - the hash database API
7
10 Hash database is a file containing a hash table and is handled with the
11 hash database API.
12 To use the hash database API, include `tcutil.h', `tchdb.h', and
14 related standard header files. Usually, write the following descrip‐
15 tion near the front of a source file.
16 #include <tcutil.h>
18 #include <tchdb.h>
19 #include <stdlib.h>
20 #include <time.h>
21 #include <stdbool.h>
22 #include <stdint.h>
23 Objects whose type is pointer to `TCHDB' are used to handle hash data‐
25 bases. A hash database object is created with the function `tchdbnew'
26 and is deleted with the function `tchdbdel'. To avoid memory leak, it
27 is important to delete every object when it is no longer in use.
28 Before operations to store or retrieve records, it is necessary to open
30 a database file and connect the hash database object to it. The func‐
31 tion `tchdbopen' is used to open a database file and the function
32 `tchdbclose' is used to close the database file. To avoid data missing
33 or corruption, it is important to close every database file when it is
34 no longer in use. It is forbidden for multible database objects in a
35 process to open the same database at the same time.
36
39 The function `tchdberrmsg' is used in order to get the message string
40 corresponding to an error code.
41 const char *tchdberrmsg(int ecode);
43 `ecode' specifies the error code.
44 The return value is the message string of the error code.
45 The function `tchdbnew' is used in order to create a hash database
47 object.
48 TCHDB *tchdbnew(void);
50 The return value is the new hash database object.
51 The function `tchdbdel' is used in order to delete a hash database
53 object.
54 void tchdbdel(TCHDB *hdb);
56 `hdb' specifies the hash database object.
57 If the database is not closed, it is closed implicitly.
58 Note that the deleted object and its derivatives can not
59 be used anymore.
60 The function `tchdbecode' is used in order to get the last happened
62 error code of a hash database object.
63 int tchdbecode(TCHDB *hdb);
65 `hdb' specifies the hash database object.
66 The return value is the last happened error code.
67 The following error codes are defined: `TCESUCCESS' for
68 success, `TCETHREAD' for threading error, `TCEINVALID'
69 for invalid operation, `TCENOFILE' for file not found,
70 `TCENOPERM' for no permission, `TCEMETA' for invalid meta
71 data, `TCERHEAD' for invalid record header, `TCEOPEN' for
72 open error, `TCECLOSE' for close error, `TCETRUNC' for
73 trunc error, `TCESYNC' for sync error, `TCESTAT' for stat
74 error, `TCESEEK' for seek error, `TCEREAD' for read
75 error, `TCEWRITE' for write error, `TCEMMAP' for mmap
76 error, `TCELOCK' for lock error, `TCEUNLINK' for unlink
77 error, `TCERENAME' for rename error, `TCEMKDIR' for mkdir
78 error, `TCERMDIR' for rmdir error, `TCEKEEP' for existing
79 record, `TCENOREC' for no record found, and `TCEMISC' for
80 miscellaneous error.
81 The function `tchdbsetmutex' is used in order to set mutual exclusion
83 control of a hash database object for threading.
84 bool tchdbsetmutex(TCHDB *hdb);
86 `hdb' specifies the hash database object which is not
87 opened.
88 If successful, the return value is true, else, it is
89 false.
90 Note that the mutual exclusion control of the database
91 should be set before the database is opened.
92 The function `tchdbtune' is used in order to set the tuning parameters
94 of a hash database object.
95 bool tchdbtune(TCHDB *hdb, int64_t bnum, int8_t apow, int8_t
97 fpow, uint8_t opts);
98 `hdb' specifies the hash database object which is not
99 opened.
100 `bnum' specifies the number of elements of the bucket
101 array. If it is not more than 0, the default value is
102 specified. The default value is 16381. Suggested size
103 of the bucket array is about from 0.5 to 4 times of the
104 number of all records to be stored.
105 `apow' specifies the size of record alignment by power of
106 2. If it is negative, the default value is specified.
107 The default value is 4 standing for 2^4=16.
108 `fpow' specifies the maximum number of elements of the
109 free block pool by power of 2. If it is negative, the
110 default value is specified. The default value is 10
111 standing for 2^10=1024.
112 `opts' specifies options by bitwise-or: `HDBTLARGE' spec‐
113 ifies that the size of the database can be larger than
114 2GB by using 64-bit bucket array, `HDBTDEFLATE' specifies
115 that each record is compressed with Deflate encoding,
116 `HDBTBZIP' specifies that each record is compressed with
117 BZIP2 encoding, `HDBTTCBS' specifies that each record is
118 compressed with TCBS encoding.
119 If successful, the return value is true, else, it is
120 false.
121 Note that the tuning parameters should be set before the
122 database is opened.
123 The function `tchdbsetcache' is used in order to set the caching param‐
125 eters of a hash database object.
126 bool tchdbsetcache(TCHDB *hdb, int32_t rcnum);
128 `hdb' specifies the hash database object which is not
129 opened.
130 `rcnum' specifies the maximum number of records to be
131 cached. If it is not more than 0, the record cache is
132 disabled. It is disabled by default.
133 If successful, the return value is true, else, it is
134 false.
135 Note that the caching parameters should be set before the
136 database is opened.
137 The function `tchdbsetxmsiz' is used in order to set the size of the
139 extra mapped memory of a hash database object.
140 bool tchdbsetxmsiz(TCHDB *hdb, int64_t xmsiz);
142 `hdb' specifies the hash database object which is not
143 opened.
144 `xmsiz' specifies the size of the extra mapped memory.
145 If it is not more than 0, the extra mapped memory is dis‐
146 abled. The default size is 67108864.
147 If successful, the return value is true, else, it is
148 false.
149 Note that the mapping parameters should be set before the
150 database is opened.
151 The function `tchdbsetdfunit' is used in order to set the unit step
153 number of auto defragmentation of a hash database object.
154 bool tchdbsetdfunit(TCHDB *hdb, int32_t dfunit);
156 `hdb' specifies the hash database object which is not
157 opened.
158 `dfunit' specifie the unit step number. If it is not
159 more than 0, the auto defragmentation is disabled. It is
160 disabled by default.
161 If successful, the return value is true, else, it is
162 false.
163 Note that the defragmentation parameters should be set
164 before the database is opened.
165 The function `tchdbopen' is used in order to open a database file and
167 connect a hash database object.
168 bool tchdbopen(TCHDB *hdb, const char *path, int omode);
170 `hdb' specifies the hash database object which is not
171 opened.
172 `path' specifies the path of the database file.
173 `omode' specifies the connection mode: `HDBOWRITER' as a
174 writer, `HDBOREADER' as a reader. If the mode is
175 `HDBOWRITER', the following may be added by bitwise-or:
176 `HDBOCREAT', which means it creates a new database if not
177 exist, `HDBOTRUNC', which means it creates a new database
178 regardless if one exists, `HDBOTSYNC', which means every
179 transaction synchronizes updated contents with the
180 device. Both of `HDBOREADER' and `HDBOWRITER' can be
181 added to by bitwise-or: `HDBONOLCK', which means it opens
182 the database file without file locking, or `HDBOLCKNB',
183 which means locking is performed without blocking.
184 If successful, the return value is true, else, it is
185 false.
186 The function `tchdbclose' is used in order to close a hash database
188 object.
189 bool tchdbclose(TCHDB *hdb);
191 `hdb' specifies the hash database object.
192 If successful, the return value is true, else, it is
193 false.
194 Update of a database is assured to be written when the
195 database is closed. If a writer opens a database but
196 does not close it appropriately, the database will be
197 broken.
198 The function `tchdbput' is used in order to store a record into a hash
200 database object.
201 bool tchdbput(TCHDB *hdb, const void *kbuf, int ksiz, const void
203 *vbuf, int vsiz);
204 `hdb' specifies the hash database object connected as a
205 writer.
206 `kbuf' specifies the pointer to the region of the key.
207 `ksiz' specifies the size of the region of the key.
208 `vbuf' specifies the pointer to the region of the value.
209 `vsiz' specifies the size of the region of the value.
210 If successful, the return value is true, else, it is
211 false.
212 If a record with the same key exists in the database, it
213 is overwritten.
214 The function `tchdbput2' is used in order to store a string record into
216 a hash database object.
217 bool tchdbput2(TCHDB *hdb, const char *kstr, const char *vstr);
219 `hdb' specifies the hash database object connected as a
220 writer.
221 `kstr' specifies the string of the key.
222 `vstr' specifies the string of the value.
223 If successful, the return value is true, else, it is
224 false.
225 If a record with the same key exists in the database, it
226 is overwritten.
227 The function `tchdbputkeep' is used in order to store a new record into
229 a hash database object.
230 bool tchdbputkeep(TCHDB *hdb, const void *kbuf, int ksiz, const
232 void *vbuf, int vsiz);
233 `hdb' specifies the hash database object connected as a
234 writer.
235 `kbuf' specifies the pointer to the region of the key.
236 `ksiz' specifies the size of the region of the key.
237 `vbuf' specifies the pointer to the region of the value.
238 `vsiz' specifies the size of the region of the value.
239 If successful, the return value is true, else, it is
240 false.
241 If a record with the same key exists in the database,
242 this function has no effect.
243 The function `tchdbputkeep2' is used in order to store a new string
245 record into a hash database object.
246 bool tchdbputkeep2(TCHDB *hdb, const char *kstr, const char
248 *vstr);
249 `hdb' specifies the hash database object connected as a
250 writer.
251 `kstr' specifies the string of the key.
252 `vstr' specifies the string of the value.
253 If successful, the return value is true, else, it is
254 false.
255 If a record with the same key exists in the database,
256 this function has no effect.
257 The function `tchdbputcat' is used in order to concatenate a value at
259 the end of the existing record in a hash database object.
260 bool tchdbputcat(TCHDB *hdb, const void *kbuf, int ksiz, const
262 void *vbuf, int vsiz);
263 `hdb' specifies the hash database object connected as a
264 writer.
265 `kbuf' specifies the pointer to the region of the key.
266 `ksiz' specifies the size of the region of the key.
267 `vbuf' specifies the pointer to the region of the value.
268 `vsiz' specifies the size of the region of the value.
269 If successful, the return value is true, else, it is
270 false.
271 If there is no corresponding record, a new record is cre‐
272 ated.
273 The function `tchdbputcat2' is used in order to concatenate a string
275 value at the end of the existing record in a hash database object.
276 bool tchdbputcat2(TCHDB *hdb, const char *kstr, const char
278 *vstr);
279 `hdb' specifies the hash database object connected as a
280 writer.
281 `kstr' specifies the string of the key.
282 `vstr' specifies the string of the value.
283 If successful, the return value is true, else, it is
284 false.
285 If there is no corresponding record, a new record is cre‐
286 ated.
287 The function `tchdbputasync' is used in order to store a record into a
289 hash database object in asynchronous fashion.
290 bool tchdbputasync(TCHDB *hdb, const void *kbuf, int ksiz, const
292 void *vbuf, int vsiz);
293 `hdb' specifies the hash database object connected as a
294 writer.
295 `kbuf' specifies the pointer to the region of the key.
296 `ksiz' specifies the size of the region of the key.
297 `vbuf' specifies the pointer to the region of the value.
298 `vsiz' specifies the size of the region of the value.
299 If successful, the return value is true, else, it is
300 false.
301 If a record with the same key exists in the database, it
302 is overwritten. Records passed to this function are
303 accumulated into the inner buffer and wrote into the file
304 at a blast.
305 The function `tchdbputasync2' is used in order to store a string record
307 into a hash database object in asynchronous fashion.
308 bool tchdbputasync2(TCHDB *hdb, const char *kstr, const char
310 *vstr);
311 `hdb' specifies the hash database object connected as a
312 writer.
313 `kstr' specifies the string of the key.
314 `vstr' specifies the string of the value.
315 If successful, the return value is true, else, it is
316 false.
317 If a record with the same key exists in the database, it
318 is overwritten. Records passed to this function are
319 accumulated into the inner buffer and wrote into the file
320 at a blast.
321 The function `tchdbout' is used in order to remove a record of a hash
323 database object.
324 bool tchdbout(TCHDB *hdb, const void *kbuf, int ksiz);
326 `hdb' specifies the hash database object connected as a
327 writer.
328 `kbuf' specifies the pointer to the region of the key.
329 `ksiz' specifies the size of the region of the key.
330 If successful, the return value is true, else, it is
331 false.
332 The function `tchdbout2' is used in order to remove a string record of
334 a hash database object.
335 bool tchdbout2(TCHDB *hdb, const char *kstr);
337 `hdb' specifies the hash database object connected as a
338 writer.
339 `kstr' specifies the string of the key.
340 If successful, the return value is true, else, it is
341 false.
342 The function `tchdbget' is used in order to retrieve a record in a hash
344 database object.
345 void *tchdbget(TCHDB *hdb, const void *kbuf, int ksiz, int *sp);
347 `hdb' specifies the hash database object.
348 `kbuf' specifies the pointer to the region of the key.
349 `ksiz' specifies the size of the region of the key.
350 `sp' specifies the pointer to the variable into which the
351 size of the region of the return value is assigned.
352 If successful, the return value is the pointer to the
353 region of the value of the corresponding record. `NULL'
354 is returned if no record corresponds.
355 Because an additional zero code is appended at the end of
356 the region of the return value, the return value can be
357 treated as a character string. Because the region of the
358 return value is allocated with the `malloc' call, it
359 should be released with the `free' call when it is no
360 longer in use.
361 The function `tchdbget2' is used in order to retrieve a string record
363 in a hash database object.
364 char *tchdbget2(TCHDB *hdb, const char *kstr);
366 `hdb' specifies the hash database object.
367 `kstr' specifies the string of the key.
368 If successful, the return value is the string of the
369 value of the corresponding record. `NULL' is returned if
370 no record corresponds.
371 Because the region of the return value is allocated with
372 the `malloc' call, it should be released with the `free'
373 call when it is no longer in use.
374 The function `tchdbget3' is used in order to retrieve a record in a
376 hash database object and write the value into a buffer.
377 int tchdbget3(TCHDB *hdb, const void *kbuf, int ksiz, void
379 *vbuf, int max);
380 `hdb' specifies the hash database object.
381 `kbuf' specifies the pointer to the region of the key.
382 `ksiz' specifies the size of the region of the key.
383 `vbuf' specifies the pointer to the buffer into which the
384 value of the corresponding record is written.
385 `max' specifies the size of the buffer.
386 If successful, the return value is the size of the writ‐
387 ten data, else, it is -1. -1 is returned if no record
388 corresponds to the specified key.
389 Note that an additional zero code is not appended at the
390 end of the region of the writing buffer.
391 The function `tchdbvsiz' is used in order to get the size of the value
393 of a record in a hash database object.
394 int tchdbvsiz(TCHDB *hdb, const void *kbuf, int ksiz);
396 `hdb' specifies the hash database object.
397 `kbuf' specifies the pointer to the region of the key.
398 `ksiz' specifies the size of the region of the key.
399 If successful, the return value is the size of the value
400 of the corresponding record, else, it is -1.
401 The function `tchdbvsiz2' is used in order to get the size of the value
403 of a string record in a hash database object.
404 int tchdbvsiz2(TCHDB *hdb, const char *kstr);
406 `hdb' specifies the hash database object.
407 `kstr' specifies the string of the key.
408 If successful, the return value is the size of the value
409 of the corresponding record, else, it is -1.
410 The function `tchdbiterinit' is used in order to initialize the itera‐
412 tor of a hash database object.
413 bool tchdbiterinit(TCHDB *hdb);
415 `hdb' specifies the hash database object.
416 If successful, the return value is true, else, it is
417 false.
418 The iterator is used in order to access the key of every
419 record stored in a database.
420 The function `tchdbiternext' is used in order to get the next key of
422 the iterator of a hash database object.
423 void *tchdbiternext(TCHDB *hdb, int *sp);
425 `hdb' specifies the hash database object.
426 `sp' specifies the pointer to the variable into which the
427 size of the region of the return value is assigned.
428 If successful, the return value is the pointer to the
429 region of the next key, else, it is `NULL'. `NULL' is
430 returned when no record is to be get out of the iterator.
431 Because an additional zero code is appended at the end of
432 the region of the return value, the return value can be
433 treated as a character string. Because the region of the
434 return value is allocated with the `malloc' call, it
435 should be released with the `free' call when it is no
436 longer in use. It is possible to access every record by
437 iteration of calling this function. It is allowed to
438 update or remove records whose keys are fetched while the
439 iteration. However, it is not assured if updating the
440 database is occurred while the iteration. Besides, the
441 order of this traversal access method is arbitrary, so it
442 is not assured that the order of storing matches the one
443 of the traversal access.
444 The function `tchdbiternext2' is used in order to get the next key
446 string of the iterator of a hash database object.
447 char *tchdbiternext2(TCHDB *hdb);
449 `hdb' specifies the hash database object.
450 If successful, the return value is the string of the next
451 key, else, it is `NULL'. `NULL' is returned when no
452 record is to be get out of the iterator.
453 Because the region of the return value is allocated with
454 the `malloc' call, it should be released with the `free'
455 call when it is no longer in use. It is possible to
456 access every record by iteration of calling this func‐
457 tion. However, it is not assured if updating the data‐
458 base is occurred while the iteration. Besides, the order
459 of this traversal access method is arbitrary, so it is
460 not assured that the order of storing matches the one of
461 the traversal access.
462 The function `tchdbiternext3' is used in order to get the next extensi‐
464 ble objects of the iterator of a hash database object.
465 bool tchdbiternext3(TCHDB *hdb, TCXSTR *kxstr, TCXSTR *vxstr);
467 `hdb' specifies the hash database object.
468 `kxstr' specifies the object into which the next key is
469 wrote down.
470 `vxstr' specifies the object into which the next value is
471 wrote down.
472 If successful, the return value is true, else, it is
473 false. False is returned when no record is to be get out
474 of the iterator.
475 The function `tchdbfwmkeys' is used in order to get forward matching
477 keys in a hash database object.
478 TCLIST *tchdbfwmkeys(TCHDB *hdb, const void *pbuf, int psiz, int
480 max);
481 `hdb' specifies the hash database object.
482 `pbuf' specifies the pointer to the region of the prefix.
483 `psiz' specifies the size of the region of the prefix.
484 `max' specifies the maximum number of keys to be fetched.
485 If it is negative, no limit is specified.
486 The return value is a list object of the corresponding
487 keys. This function does never fail. It returns an
488 empty list even if no key corresponds.
489 Because the object of the return value is created with
490 the function `tclistnew', it should be deleted with the
491 function `tclistdel' when it is no longer in use. Note
492 that this function may be very slow because every key in
493 the database is scanned.
494 The function `tchdbfwmkeys2' is used in order to get forward matching
496 string keys in a hash database object.
497 TCLIST *tchdbfwmkeys2(TCHDB *hdb, const char *pstr, int max);
499 `hdb' specifies the hash database object.
500 `pstr' specifies the string of the prefix.
501 `max' specifies the maximum number of keys to be fetched.
502 If it is negative, no limit is specified.
503 The return value is a list object of the corresponding
504 keys. This function does never fail. It returns an
505 empty list even if no key corresponds.
506 Because the object of the return value is created with
507 the function `tclistnew', it should be deleted with the
508 function `tclistdel' when it is no longer in use. Note
509 that this function may be very slow because every key in
510 the database is scanned.
511 The function `tchdbaddint' is used in order to add an integer to a
513 record in a hash database object.
514 int tchdbaddint(TCHDB *hdb, const void *kbuf, int ksiz, int
516 num);
517 `hdb' specifies the hash database object connected as a
518 writer.
519 `kbuf' specifies the pointer to the region of the key.
520 `ksiz' specifies the size of the region of the key.
521 `num' specifies the additional value.
522 If successful, the return value is the summation value,
523 else, it is `INT_MIN'.
524 If the corresponding record exists, the value is treated
525 as an integer and is added to. If no record corresponds,
526 a new record of the additional value is stored.
527 The function `tchdbdbadddouble' is used in order to add a real number
529 to a record in a hash database object.
530 double tchdbadddouble(TCHDB *hdb, const void *kbuf, int ksiz,
532 double num);
533 `hdb' specifies the hash database object connected as a
534 writer.
535 `kbuf' specifies the pointer to the region of the key.
536 `ksiz' specifies the size of the region of the key.
537 `num' specifies the additional value.
538 If successful, the return value is the summation value,
539 else, it is Not-a-Number.
540 If the corresponding record exists, the value is treated
541 as a real number and is added to. If no record corre‐
542 sponds, a new record of the additional value is stored.
543 The function `tchdbsync' is used in order to synchronize updated con‐
545 tents of a hash database object with the file and the device.
546 bool tchdbsync(TCHDB *hdb);
548 `hdb' specifies the hash database object connected as a
549 writer.
550 If successful, the return value is true, else, it is
551 false.
552 This function is useful when another process connects to
553 the same database file.
554 The function `tchdboptimize' is used in order to optimize the file of a
556 hash database object.
557 bool tchdboptimize(TCHDB *hdb, int64_t bnum, int8_t apow, int8_t
559 fpow, uint8_t opts);
560 `hdb' specifies the hash database object connected as a
561 writer.
562 `bnum' specifies the number of elements of the bucket
563 array. If it is not more than 0, the default value is
564 specified. The default value is two times of the number
565 of records.
566 `apow' specifies the size of record alignment by power of
567 2. If it is negative, the current setting is not
568 changed.
569 `fpow' specifies the maximum number of elements of the
570 free block pool by power of 2. If it is negative, the
571 current setting is not changed.
572 `opts' specifies options by bitwise-or: `HDBTLARGE' spec‐
573 ifies that the size of the database can be larger than
574 2GB by using 64-bit bucket array, `HDBTDEFLATE' specifies
575 that each record is compressed with Deflate encoding,
576 `HDBTBZIP' specifies that each record is compressed with
577 BZIP2 encoding, `HDBTTCBS' specifies that each record is
578 compressed with TCBS encoding. If it is `UINT8_MAX', the
579 current setting is not changed.
580 If successful, the return value is true, else, it is
581 false.
582 This function is useful to reduce the size of the data‐
583 base file with data fragmentation by successive updating.
584 The function `tchdbvanish' is used in order to remove all records of a
586 hash database object.
587 bool tchdbvanish(TCHDB *hdb);
589 `hdb' specifies the hash database object connected as a
590 writer.
591 If successful, the return value is true, else, it is
592 false.
593 The function `tchdbcopy' is used in order to copy the database file of
595 a hash database object.
596 bool tchdbcopy(TCHDB *hdb, const char *path);
598 `hdb' specifies the hash database object.
599 `path' specifies the path of the destination file. If it
600 begins with `@', the trailing substring is executed as a
601 command line.
602 If successful, the return value is true, else, it is
603 false. False is returned if the executed command returns
604 non-zero code.
605 The database file is assured to be kept synchronized and
606 not modified while the copying or executing operation is
607 in progress. So, this function is useful to create a
608 backup file of the database file.
609 The function `tchdbtranbegin' is used in order to begin the transaction
611 of a hash database object.
612 bool tchdbtranbegin(TCHDB *hdb);
614 `hdb' specifies the hash database object connected as a
615 writer.
616 If successful, the return value is true, else, it is
617 false.
618 The database is locked by the thread while the transac‐
619 tion so that only one transaction can be activated with a
620 database object at the same time. Thus, the serializable
621 isolation level is assumed if every database operation is
622 performed in the transaction. All updated regions are
623 kept track of by write ahead logging while the transac‐
624 tion. If the database is closed during transaction, the
625 transaction is aborted implicitly.
626 The function `tchdbtrancommit' is used in order to commit the transac‐
628 tion of a hash database object.
629 bool tchdbtrancommit(TCHDB *hdb);
631 `hdb' specifies the hash database object connected as a
632 writer.
633 If successful, the return value is true, else, it is
634 false.
635 Update in the transaction is fixed when it is committed
636 successfully.
637 The function `tchdbtranabort' is used in order to abort the transaction
639 of a hash database object.
640 bool tchdbtranabort(TCHDB *hdb);
642 `hdb' specifies the hash database object connected as a
643 writer.
644 If successful, the return value is true, else, it is
645 false.
646 Update in the transaction is discarded when it is
647 aborted. The state of the database is rollbacked to
648 before transaction.
649 The function `tchdbpath' is used in order to get the file path of a
651 hash database object.
652 const char *tchdbpath(TCHDB *hdb);
654 `hdb' specifies the hash database object.
655 The return value is the path of the database file or
656 `NULL' if the object does not connect to any database
657 file.
658 The function `tchdbrnum' is used in order to get the number of records
660 of a hash database object.
661 uint64_t tchdbrnum(TCHDB *hdb);
663 `hdb' specifies the hash database object.
664 The return value is the number of records or 0 if the
665 object does not connect to any database file.
666 The function `tchdbfsiz' is used in order to get the size of the data‐
668 base file of a hash database object.
669 uint64_t tchdbfsiz(TCHDB *hdb);
671 `hdb' specifies the hash database object.
672 The return value is the size of the database file or 0 if
673 the object does not connect to any database file.
674
677 tchtest(1), tchmttest(1), tchmgr(1), tokyocabinet(3)
678Man Page 2012-08-18 TCHDB(3)