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CentOS 7.0 - man page for tcbdb (centos section 3)

TCBDB(3)				  Tokyo Cabinet 				 TCBDB(3)

NAME
       tcbdb - the B+ tree database API

DESCRIPTION
       B+  tree  database is a file containing a B+ tree and is handled with the B+ tree database
       API.

       To use the B+ tree database API,  include  `tcutil.h',  `tcbdb.h',  and	related  standard
       header files.  Usually, write the following description near the front of a source file.

	      #include <tcutil.h>
	      #include <tcbdb.h>
	      #include <stdlib.h>
	      #include <time.h>
	      #include <stdbool.h>
	      #include <stdint.h>

       Objects	whose type is pointer to `TCBDB' are used to handle B+ tree databases.	A B+ tree
       database object is created with the function `tcbdbnew' and is deleted with  the  function
       `tcbdbdel'.   To  avoid	memory leak, it is important to delete every object when it is no
       longer in use.

       Before operations to store or retrieve records, it is necessary to open	a  database  file
       and connect the B+ tree database object to it.  The function `tcbdbopen' is used to open a
       database file and the function `tcbdbclose' is used to close the database file.	To  avoid
       data  missing  or  corruption,  it is important to close every database file when it is no
       longer in use.  It is forbidden for multible database objects in a  process  to	open  the
       same database at the same time.

API
       The  function `tcbdberrmsg' is used in order to get the message string corresponding to an
       error code.

	      const char *tcbdberrmsg(int ecode);
		     `ecode' specifies the error code.
		     The return value is the message string of the error code.

       The function `tcbdbnew' is used in order to create a B+ tree database object.

	      TCBDB *tcbdbnew(void);
		     The return value is the new B+ tree database object.

       The function `tcbdbdel' is used in order to delete a B+ tree database object.

	      void tcbdbdel(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object.
		     If the database is not closed, it	is  closed  implicitly.   Note	that  the
		     deleted object and its derivatives can not be used anymore.

       The  function  `tcbdbecode'  is	used in order to get the last happened error code of a B+
       tree database object.

	      int tcbdbecode(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object.
		     The return value is the last happened error code.
		     The following error codes are defined: `TCESUCCESS' for success, `TCETHREAD'
		     for  threading  error,  `TCEINVALID'  for invalid operation, `TCENOFILE' for
		     file not found, `TCENOPERM' for no permission, `TCEMETA'  for  invalid  meta
		     data,  `TCERHEAD' for invalid record header, `TCEOPEN' for open error, `TCE-
		     CLOSE' for close error, `TCETRUNC'  for  trunc  error,  `TCESYNC'	for  sync
		     error,  `TCESTAT'	for  stat  error, `TCESEEK' for seek error, `TCEREAD' for
		     read error, `TCEWRITE' for write error, `TCEMMAP' for mmap error,	`TCELOCK'
		     for  lock error, `TCEUNLINK' for unlink error, `TCERENAME' for rename error,
		     `TCEMKDIR' for mkdir error, `TCERMDIR' for rmdir error, `TCEKEEP' for exist-
		     ing  record, `TCENOREC' for no record found, and `TCEMISC' for miscellaneous
		     error.

       The function `tcbdbsetmutex' is used in order to set mutual exclusion control of a B+ tree
       database object for threading.

	      bool tcbdbsetmutex(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object which is not opened.
		     If successful, the return value is true, else, it is false.
		     Note  that the mutual exclusion control of the database should be set before
		     the database is opened.

       The function `tcbdbsetcmpfunc' is used in order to set the custom comparison function of a
       B+ tree database object.

	      bool tcbdbsetcmpfunc(TCBDB *bdb, TCCMP cmp, void *cmpop);
		     `bdb' specifies the B+ tree database object which is not opened.
		     `cmp'  specifies the pointer to the custom comparison function.  It receives
		     five parameters.  The first parameter is the pointer to the  region  of  one
		     key.   The second parameter is the size of the region of one key.	The third
		     parameter is the pointer to the region of the other key.  The fourth parame-
		     ter  is the size of the region of the other key.  The fifth parameter is the
		     pointer to the optional opaque object.  It returns positive if the former is
		     big, negative if the latter is big, 0 if both are equivalent.
		     `cmpop'  specifies  an  arbitrary	pointer to be given as a parameter of the
		     comparison function.  If it is not needed, `NULL' can be specified.
		     If successful, the return value is true, else, it is false.
		     The default comparison function compares keys  of	two  records  by  lexical
		     order.	The    functions    `tccmplexical'   (dafault),   `tccmpdecimal',
		     `tccmpint32', and `tccmpint64' are built-in.  Note that the comparison func-
		     tion  should  be  set before the database is opened.  Moreover, user-defined
		     comparison functions should be set every time the database is being opened.

       The function `tcbdbtune' is used in order to set the tuning parameters of a B+ tree  data-
       base object.

	      bool tcbdbtune(TCBDB *bdb, int32_t lmemb, int32_t nmemb, int64_t bnum, int8_t apow,
	      int8_t fpow, uint8_t opts);
		     `bdb' specifies the B+ tree database object which is not opened.
		     `lmemb' specifies the number of members in each leaf page.   If  it  is  not
		     more than 0, the default value is specified.  The default value is 128.
		     `nmemb' specifies the number of members in each non-leaf page.  If it is not
		     more than 0, the default value is specified.  The default value is 256.
		     `bnum' specifies the number of elements of the bucket array.  If it  is  not
		     more  than  0,  the default value is specified.  The default value is 16381.
		     Suggested size of the bucket array is about from 1 to 4 times of the  number
		     of all pages to be stored.
		     `apow' specifies the size of record alignment by power of 2.  If it is nega-
		     tive, the default value is specified.  The default value is 8  standing  for
		     2^8=256.
		     `fpow'  specifies	the  maximum number of elements of the free block pool by
		     power of 2.  If it is negative, the default value is specified.  The default
		     value is 10 standing for 2^10=1024.
		     `opts'  specifies options by bitwise-or: `BDBTLARGE' specifies that the size
		     of the database can be larger than 2GB by using 64-bit bucket array,  `BDBT-
		     DEFLATE'  specifies  that	each  page  is	compressed with Deflate encoding,
		     `BDBTBZIP' specifies that each  page  is  compressed  with  BZIP2	encoding,
		     `BDBTTCBS' specifies that each page is compressed with TCBS encoding.
		     If successful, the return value is true, else, it is false.
		     Note that the tuning parameters should be set before the database is opened.

       The  function  `tcbdbsetcache' is used in order to set the caching parameters of a B+ tree
       database object.

	      bool tcbdbsetcache(TCBDB *bdb, int32_t lcnum, int32_t ncnum);
		     `bdb' specifies the B+ tree database object which is not opened.
		     `lcnum' specifies the maximum number of leaf nodes to be cached.  If  it  is
		     not more than 0, the default value is specified.  The default value is 1024.
		     `ncnum'  specifies the maximum number of non-leaf nodes to be cached.  If it
		     is not more than 0, the default value is specified.  The  default	value  is
		     512.
		     If successful, the return value is true, else, it is false.
		     Note  that  the  caching  parameters  should  be  set before the database is
		     opened.

       The function `tcbdbsetxmsiz' is used in order to set the size of the extra  mapped  memory
       of a B+ tree database object.

	      bool tcbdbsetxmsiz(TCBDB *bdb, int64_t xmsiz);
		     `bdb' specifies the B+ tree database object which is not opened.
		     `xmsiz'  specifies  the  size of the extra mapped memory.	If it is not more
		     than 0, the extra mapped memory is disabled.  It is disabled by default.
		     If successful, the return value is true, else, it is false.
		     Note that the mapping parameters  should  be  set	before	the  database  is
		     opened.

       The function `tcbdbsetdfunit' is used in order to set the unit step number of auto defrag-
       mentation of a B+ tree database object.

	      bool tcbdbsetdfunit(TCBDB *bdb, int32_t dfunit);
		     `bdb' specifies the B+ tree database object which is not opened.
		     `dfunit' specifie the unit step number.  If it is not more than 0, the  auto
		     defragmentation is disabled.  It is disabled by default.
		     If successful, the return value is true, else, it is false.
		     Note that the defragmentation parameter should be set before the database is
		     opened.

       The function `tcbdbopen' is used in order to open a database file and connect  a  B+  tree
       database object.

	      bool tcbdbopen(TCBDB *bdb, const char *path, int omode);
		     `bdb' specifies the B+ tree database object which is not opened.
		     `path' specifies the path of the database file.
		     `omode'  specifies  the  connection mode: `BDBOWRITER' as a writer, `BDBORE-
		     ADER' as a reader.  If the mode is `BDBOWRITER', the following may be  added
		     by  bitwise-or:  `BDBOCREAT',  which  means it creates a new database if not
		     exist, `BDBOTRUNC', which means it creates a new database regardless if  one
		     exists, `BDBOTSYNC', which means every transaction synchronizes updated con-
		     tents with the device.  Both of `BDBOREADER' and `BDBOWRITER' can	be  added
		     to  by bitwise-or: `BDBONOLCK', which means it opens the database file with-
		     out file locking, or `BDBOLCKNB', which means locking is  performed  without
		     blocking.
		     If successful, the return value is true, else, it is false.

       The function `tcbdbclose' is used in order to close a B+ tree database object.

	      bool tcbdbclose(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object.
		     If successful, the return value is true, else, it is false.
		     Update  of  a database is assured to be written when the database is closed.
		     If a writer opens a database but does not close it appropriately, the  data-
		     base will be broken.

       The function `tcbdbput' is used in order to store a record into a B+ tree database object.

	      bool tcbdbput(TCBDB *bdb, const void *kbuf, int ksiz, const void *vbuf, int vsiz);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `vbuf' specifies the pointer to the region of the value.
		     `vsiz' specifies the size of the region of the value.
		     If successful, the return value is true, else, it is false.
		     If a record with the same key exists in the database, it is overwritten.

       The function `tcbdbput2' is used in order to store a string record into a B+ tree database
       object.

	      bool tcbdbput2(TCBDB *bdb, const char *kstr, const char *vstr);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kstr' specifies the string of the key.
		     `vstr' specifies the string of the value.
		     If successful, the return value is true, else, it is false.
		     If a record with the same key exists in the database, it is overwritten.

       The function `tcbdbputkeep' is used in order to store a new record into a B+ tree database
       object.

	      bool  tcbdbputkeep(TCBDB	*bdb,  const  void *kbuf, int ksiz, const void *vbuf, int
	      vsiz);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `vbuf' specifies the pointer to the region of the value.
		     `vsiz' specifies the size of the region of the value.
		     If successful, the return value is true, else, it is false.
		     If a record with the same key exists in the database, this function  has  no
		     effect.

       The  function `tcbdbputkeep2' is used in order to store a new string record into a B+ tree
       database object.

	      bool tcbdbputkeep2(TCBDB *bdb, const char *kstr, const char *vstr);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kstr' specifies the string of the key.
		     `vstr' specifies the string of the value.
		     If successful, the return value is true, else, it is false.
		     If a record with the same key exists in the database, this function  has  no
		     effect.

       The  function  `tcbdbputcat'  is  used  in  order to concatenate a value at the end of the
       existing record in a B+ tree database object.

	      bool tcbdbputcat(TCBDB *bdb, const void *kbuf, int  ksiz,  const	void  *vbuf,  int
	      vsiz);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `vbuf' specifies the pointer to the region of the value.
		     `vsiz' specifies the size of the region of the value.
		     If successful, the return value is true, else, it is false.
		     If there is no corresponding record, a new record is created.

       The  function  `tcbdbputcat2' is used in order to concatenate a string value at the end of
       the existing record in a B+ tree database object.

	      bool tcbdbputcat2(TCBDB *bdb, const char *kstr, const char *vstr);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kstr' specifies the string of the key.
		     `vstr' specifies the string of the value.
		     If successful, the return value is true, else, it is false.
		     If there is no corresponding record, a new record is created.

       The function `tcbdbputdup' is used in order to store a record  into  a  B+  tree  database
       object with allowing duplication of keys.

	      bool  tcbdbputdup(TCBDB  *bdb,  const  void  *kbuf, int ksiz, const void *vbuf, int
	      vsiz);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `vbuf' specifies the pointer to the region of the value.
		     `vsiz' specifies the size of the region of the value.
		     If successful, the return value is true, else, it is false.
		     If a record with the same key exists in the  database,  the  new  record  is
		     placed after the existing one.

       The function `tcbdbputdup2' is used in order to store a string record into a B+ tree data-
       base object with allowing duplication of keys.

	      bool tcbdbputdup2(TCBDB *bdb, const char *kstr, const char *vstr);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kstr' specifies the string of the key.
		     `vstr' specifies the string of the value.
		     If successful, the return value is true, else, it is false.
		     If a record with the same key exists in the  database,  the  new  record  is
		     placed after the existing one.

       The  function  `tcbdbputdup3'  is  used	in order to store records into a B+ tree database
       object with allowing duplication of keys.

	      bool tcbdbputdup3(TCBDB *bdb, const void *kbuf, int ksiz, const TCLIST *vals);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the common key.
		     `ksiz' specifies the size of the region of the common key.
		     `vals' specifies a list object containing values.
		     If successful, the return value is true, else, it is false.
		     If a record with the same key exists in the database, the	new  records  are
		     placed after the existing one.

       The function `tcbdbout' is used in order to remove a record of a B+ tree database object.

	      bool tcbdbout(TCBDB *bdb, const void *kbuf, int ksiz);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     If successful, the return value is true, else, it is false.
		     If the key of duplicated records is specified, the first one is selected.

       The  function `tcbdbout2' is used in order to remove a string record of a B+ tree database
       object.

	      bool tcbdbout2(TCBDB *bdb, const char *kstr);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kstr' specifies the string of the key.
		     If successful, the return value is true, else, it is false.
		     If the key of duplicated records is specified, the first one is selected.

       The function `tcbdbout3' is used in order to remove records of a B+ tree database object.

	      bool tcbdbout3(TCBDB *bdb, const void *kbuf, int ksiz);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     If successful, the return value is true, else, it is false.
		     If the key of duplicated records is specified, all of them are removed.

       The function `tcbdbget' is used in order to retrieve  a	record	in  a  B+  tree  database
       object.

	      void *tcbdbget(TCBDB *bdb, const void *kbuf, int ksiz, int *sp);
		     `bdb' specifies the B+ tree database object.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `sp' specifies the pointer to the variable into which the size of the region
		     of the return value is assigned.
		     If successful, the return value is the pointer to the region of the value of
		     the corresponding record.	`NULL' is returned if no record corresponds.
		     If  the  key  of duplicated records is specified, the first one is selected.
		     Because an additional zero code is appended at the end of the region of  the
		     return  value,  the  return  value  can  be  treated  as a character string.
		     Because the region of the return value is allocated with the `malloc'  call,
		     it should be released with the `free' call when it is no longer in use.

       The  function  `tcbdbget2' is used in order to retrieve a string record in a B+ tree data-
       base object.

	      char *tcbdbget2(TCBDB *bdb, const char *kstr);
		     `bdb' specifies the B+ tree database object.
		     `kstr' specifies the string of the key.
		     If successful, the return value is the string of the  value  of  the  corre-
		     sponding record.  `NULL' is returned if no record corresponds.
		     If  the  key  of duplicated records is specified, the first one is selected.
		     Because the region of the return value is allocated with the `malloc'  call,
		     it should be released with the `free' call when it is no longer in use.

       The  function  `tcbdbget3'  is  used  in  order to retrieve a record in a B+ tree database
       object as a volatile buffer.

	      const void *tcbdbget3(TCBDB *bdb, const void *kbuf, int ksiz, int *sp);
		     `bdb' specifies the B+ tree database object.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `sp' specifies the pointer to the variable into which the size of the region
		     of the return value is assigned.
		     If successful, the return value is the pointer to the region of the value of
		     the corresponding record.	`NULL' is returned if no record corresponds.
		     If the key of duplicated records is specified, the first  one  is	selected.
		     Because  an additional zero code is appended at the end of the region of the
		     return value, the return  value  can  be  treated	as  a  character  string.
		     Because  the region of the return value is volatile and it may be spoiled by
		     another operation of the database, the data should be  copied  into  another
		     involatile buffer immediately.

       The  function  `tcbdbget4'  is  used  in  order	to retrieve records in a B+ tree database
       object.

	      TCLIST *tcbdbget4(TCBDB *bdb, const void *kbuf, int ksiz);
		     `bdb' specifies the B+ tree database object.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     If successful, the return value is a list object of the values of the corre-
		     sponding records.	`NULL' is returned if no record corresponds.
		     Because the object of the return value is created with the function `tclist-
		     new', it should be deleted with the  function  `tclistdel'  when  it  is  no
		     longer in use.

       The function `tcbdbvnum' is used in order to get the number of records corresponding a key
       in a B+ tree database object.

	      int tcbdbvnum(TCBDB *bdb, const void *kbuf, int ksiz);
		     `bdb' specifies the B+ tree database object.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     If successful, the return value is the number of the corresponding  records,
		     else, it is 0.

       The  function  `tcbdbvnum2'  is used in order to get the number of records corresponding a
       string key in a B+ tree database object.

	      int tcbdbvnum2(TCBDB *bdb, const char *kstr);
		     `bdb' specifies the B+ tree database object.
		     `kstr' specifies the string of the key.
		     If successful, the return value is the number of the corresponding  records,
		     else, it is 0.

       The function `tcbdbvsiz' is used in order to get the size of the value of a record in a B+
       tree database object.

	      int tcbdbvsiz(TCBDB *bdb, const void *kbuf, int ksiz);
		     `bdb' specifies the B+ tree database object.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     If successful, the return value is the size of the value of the  correspond-
		     ing record, else, it is -1.
		     If the key of duplicated records is specified, the first one is selected.

       The function `tcbdbvsiz2' is used in order to get the size of the value of a string record
       in a B+ tree database object.

	      int tcbdbvsiz2(TCBDB *bdb, const char *kstr);
		     `bdb' specifies the B+ tree database object.
		     `kstr' specifies the string of the key.
		     If successful, the return value is the size of the value of the  correspond-
		     ing record, else, it is -1.
		     If the key of duplicated records is specified, the first one is selected.

       The  function  `tcbdbrange'  is	used  in order to get keys of ranged records in a B+ tree
       database object.

	      TCLIST *tcbdbrange(TCBDB *bdb, const void *bkbuf, int bksiz, bool binc, const  void
	      *ekbuf, int eksiz, bool einc, int max);
		     `bdb' specifies the B+ tree database object.
		     `bkbuf' specifies the pointer to the region of the key of the beginning bor-
		     der.  If it is `NULL', the first record is specified.
		     `bksiz' specifies the size of the region of the beginning key.
		     `binc' specifies whether the beginning border is inclusive or not.
		     `ekbuf' specifies the pointer to the region of the key of the ending border.
		     If it is `NULL', the last record is specified.
		     `eksiz' specifies the size of the region of the ending key.
		     `einc' specifies whether the ending border is inclusive or not.
		     `max'  specifies  the  maximum number of keys to be fetched.  If it is nega-
		     tive, no limit is specified.
		     The return value is a list object of the keys of the corresponding  records.
		     This  function  does never fail.  It returns an empty list even if no record
		     corresponds.
		     Because the object of the return value is created with the function `tclist-
		     new',  it	should	be  deleted  with  the function `tclistdel' when it is no
		     longer in use.

       The function `tcbdbrange2' is used in order to get string keys of ranged records in  a  B+
       tree database object.

	      TCLIST  *tcbdbrange2(TCBDB  *bdb,  const char *bkstr, bool binc, const char *ekstr,
	      bool einc, int max);
		     `bdb' specifies the B+ tree database object.
		     `bkstr' specifies the string of the key of the beginning border.  If  it  is
		     `NULL', the first record is specified.
		     `binc' specifies whether the beginning border is inclusive or not.
		     `ekstr'  specifies  the  string  of  the key of the ending border.  If it is
		     `NULL', the last record is specified.
		     `einc' specifies whether the ending border is inclusive or not.
		     `max' specifies the maximum number of keys to be fetched.	If  it	is  nega-
		     tive, no limit is specified.
		     The  return value is a list object of the keys of the corresponding records.
		     This function does never fail.  It returns an empty list even if  no  record
		     corresponds.
		     Because the object of the return value is created with the function `tclist-
		     new', it should be deleted with the  function  `tclistdel'  when  it  is  no
		     longer in use.

       The  function  `tcbdbfwmkeys'  is  used in order to get forward matching keys in a B+ tree
       database object.

	      TCLIST *tcbdbfwmkeys(TCBDB *bdb, const void *pbuf, int psiz, int max);
		     `bdb' specifies the B+ tree database object.
		     `pbuf' specifies the pointer to the region of the prefix.
		     `psiz' specifies the size of the region of the prefix.
		     `max' specifies the maximum number of keys to be fetched.	If  it	is  nega-
		     tive, no limit is specified.
		     The  return value is a list object of the corresponding keys.  This function
		     does never fail.  It returns an empty list even if no key corresponds.
		     Because the object of the return value is created with the function `tclist-
		     new',  it	should	be  deleted  with  the function `tclistdel' when it is no
		     longer in use.

       The function `tcbdbfwmkeys2' is used in order to get forward matching string keys in a  B+
       tree database object.

	      TCLIST *tcbdbfwmkeys2(TCBDB *bdb, const char *pstr, int max);
		     `bdb' specifies the B+ tree database object.
		     `pstr' specifies the string of the prefix.
		     `max'  specifies  the  maximum number of keys to be fetched.  If it is nega-
		     tive, no limit is specified.
		     The return value is a list object of the corresponding keys.  This  function
		     does never fail.  It returns an empty list even if no key corresponds.
		     Because the object of the return value is created with the function `tclist-
		     new', it should be deleted with the  function  `tclistdel'  when  it  is  no
		     longer in use.

       The  function  `tcbdbaddint'  is  used in order to add an integer to a record in a B+ tree
       database object.

	      int tcbdbaddint(TCBDB *bdb, const void *kbuf, int ksiz, int num);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `num' specifies the additional value.
		     If successful, the  return  value	is  the  summation  value,  else,  it  is
		     `INT_MIN'.
		     If  the  corresponding record exists, the value is treated as an integer and
		     is added to.  If no record corresponds, a new record of the additional value
		     is stored.

       The  function  `tcbdbadddouble'	is used in order to add a real number to a record in a B+
       tree database object.

	      double tcbdbadddouble(TCBDB *bdb, const void *kbuf, int ksiz, double num);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     `num' specifies the additional value.
		     If successful, the return value is the summation value, else, it  is  Not-a-
		     Number.
		     If  the  corresponding  record exists, the value is treated as a real number
		     and is added to.  If no record corresponds, a new record of  the  additional
		     value is stored.

       The  function  `tcbdbsync'  is  used in order to synchronize updated contents of a B+ tree
       database object with the file and the device.

	      bool tcbdbsync(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     If successful, the return value is true, else, it is false.
		     This function is useful when another process connects to the  same  database
		     file.

       The  function  `tcbdboptimize' is used in order to optimize the file of a B+ tree database
       object.

	      bool tcbdboptimize(TCBDB *bdb, int32_t lmemb, int32_t nmemb, int64_t  bnum,  int8_t
	      apow, int8_t fpow, uint8_t opts);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     `lmemb'  specifies  the  number  of members in each leaf page.  If it is not
		     more than 0, the current setting is not changed.
		     `nmemb' specifies the number of members in each non-leaf page.  If it is not
		     more than 0, the current setting is not changed.
		     `bnum'  specifies	the number of elements of the bucket array.  If it is not
		     more than 0, the default value is specified.  The default value is two times
		     of the number of pages.
		     `apow' specifies the size of record alignment by power of 2.  If it is nega-
		     tive, the current setting is not changed.
		     `fpow' specifies the maximum number of elements of the free  block  pool  by
		     power of 2.  If it is negative, the current setting is not changed.
		     `opts'  specifies options by bitwise-or: `BDBTLARGE' specifies that the size
		     of the database can be larger than 2GB by using 64-bit bucket array,  `BDBT-
		     DEFLATE'  specifies  that	each  record is compressed with Deflate encoding,
		     `BDBTBZIP' specifies that each  page  is  compressed  with  BZIP2	encoding,
		     `BDBTTCBS' specifies that each page is compressed with TCBS encoding.  If it
		     is `UINT8_MAX', the current setting is not changed.
		     If successful, the return value is true, else, it is false.
		     This function is useful to reduce the size of the database  file  with  data
		     fragmentation by successive updating.

       The  function  `tcbdbvanish'  is used in order to remove all records of a B+ tree database
       object.

	      bool tcbdbvanish(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     If successful, the return value is true, else, it is false.

       The function `tcbdbcopy' is used in order to copy the database file of a B+ tree  database
       object.

	      bool tcbdbcopy(TCBDB *bdb, const char *path);
		     `bdb' specifies the B+ tree database object.
		     `path'  specifies	the path of the destination file.  If it begins with `@',
		     the trailing substring is executed as a command line.
		     If successful, the return value is  true,	else,  it  is  false.	False  is
		     returned if the executed command returns non-zero code.
		     The  database file is assured to be kept synchronized and not modified while
		     the copying or executing operation is in progress.   So,  this  function  is
		     useful to create a backup file of the database file.

       The function `tcbdbtranbegin' is used in order to begin the transaction of a B+ tree data-
       base object.

	      bool tcbdbtranbegin(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     If successful, the return value is true, else, it is false.
		     The database is locked by the thread while the transaction so that only  one
		     transaction can be activated with a database object at the same time.  Thus,
		     the serializable isolation level is assumed if every database  operation  is
		     performed	in the transaction.  Because all pages are cached on memory while
		     the transaction, the amount of referred records is  limited  by  the  memory
		     capacity.	 If the database is closed during transaction, the transaction is
		     aborted implicitly.

       The function `tcbdbtrancommit' is used in order to commit the transaction  of  a  B+  tree
       database object.

	      bool tcbdbtrancommit(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     If successful, the return value is true, else, it is false.
		     Update in the transaction is fixed when it is committed successfully.

       The function `tcbdbtranabort' is used in order to abort the transaction of a B+ tree data-
       base object.

	      bool tcbdbtranabort(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object connected as a writer.
		     If successful, the return value is true, else, it is false.
		     Update in the transaction is discarded when it is aborted.  The state of the
		     database is rollbacked to before transaction.

       The  function  `tcbdbpath'  is  used  in  order to get the file path of a B+ tree database
       object.

	      const char *tcbdbpath(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object.
		     The return value is the path of the database file or `NULL'  if  the  object
		     does not connect to any database file.

       The  function `tcbdbrnum' is used in order to get the number of records of a B+ tree data-
       base object.

	      uint64_t tcbdbrnum(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object.
		     The return value is the number of records or 0 if the object does	not  con-
		     nect to any database file.

       The  function  `tcbdbfsiz'  is  used in order to get the size of the database file of a B+
       tree database object.

	      uint64_t tcbdbfsiz(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object.
		     The return value is the size of the database file or 0 if	the  object  does
		     not connect to any database file.

       The function `tcbdbcurnew' is used in order to create a cursor object.

	      BDBCUR *tcbdbcurnew(TCBDB *bdb);
		     `bdb' specifies the B+ tree database object.
		     The return value is the new cursor object.
		     Note  that the cursor is available only after initialization with the `tcbd-
		     bcurfirst' or the `tcbdbcurjump' functions and so on.  Moreover,  the  posi-
		     tion of the cursor will be indefinite when the database is updated after the
		     initialization of the cursor.

       The function `tcbdbcurdel' is used in order to delete a cursor object.

	      void tcbdbcurdel(BDBCUR *cur);
		     `cur' specifies the cursor object.

       The function `tcbdbcurfirst' is used in order to move a cursor object to the first record.

	      bool tcbdbcurfirst(BDBCUR *cur);
		     `cur' specifies the cursor object.
		     If successful, the return value is  true,	else,  it  is  false.	False  is
		     returned if there is no record in the database.

       The function `tcbdbcurlast' is used in order to move a cursor object to the last record.

	      bool tcbdbcurlast(BDBCUR *cur);
		     `cur' specifies the cursor object.
		     If  successful,  the  return  value  is  true,  else, it is false.  False is
		     returned if there is no record in the database.

       The function `tcbdbcurjump' is used in order to move a  cursor  object  to  the	front  of
       records corresponding a key.

	      bool tcbdbcurjump(BDBCUR *cur, const void *kbuf, int ksiz);
		     `cur' specifies the cursor object.
		     `kbuf' specifies the pointer to the region of the key.
		     `ksiz' specifies the size of the region of the key.
		     If  successful,  the  return  value  is  true,  else, it is false.  False is
		     returned if there is no record corresponding the condition.
		     The cursor is set to the first record corresponding the key or the next sub-
		     stitute if completely matching record does not exist.

       The  function  `tcbdbcurjump2'  is  used  in order to move a cursor object to the front of
       records corresponding a key string.

	      bool tcbdbcurjump2(BDBCUR *cur, const char *kstr);
		     `cur' specifies the cursor object.
		     `kstr' specifies the string of the key.
		     If successful, the return value is  true,	else,  it  is  false.	False  is
		     returned if there is no record corresponding the condition.
		     The cursor is set to the first record corresponding the key or the next sub-
		     stitute if completely matching record does not exist.

       The function `tcbdbcurprev' is used in order to move  a	cursor	object	to  the  previous
       record.

	      bool tcbdbcurprev(BDBCUR *cur);
		     `cur' specifies the cursor object.
		     If  successful,  the  return  value  is  true,  else, it is false.  False is
		     returned if there is no previous record.

       The function `tcbdbcurnext' is used in order to move a cursor object to the next record.

	      bool tcbdbcurnext(BDBCUR *cur);
		     `cur' specifies the cursor object.
		     If successful, the return value is  true,	else,  it  is  false.	False  is
		     returned if there is no next record.

       The function `tcbdbcurput' is used in order to insert a record around a cursor object.

	      bool tcbdbcurput(BDBCUR *cur, const void *vbuf, int vsiz, int cpmode);
		     `cur' specifies the cursor object of writer connection.
		     `vbuf' specifies the pointer to the region of the value.
		     `vsiz' specifies the size of the region of the value.
		     `cpmode'  specifies  detail adjustment: `BDBCPCURRENT', which means that the
		     value of the current record is overwritten, `BDBCPBEFORE', which means  that
		     the  new  record  is inserted before the current record, `BDBCPAFTER', which
		     means that the new record is inserted after the current record.
		     If successful, the return value is  true,	else,  it  is  false.	False  is
		     returned when the cursor is at invalid position.
		     After insertion, the cursor is moved to the inserted record.

       The  function  `tcbdbcurput2'  is  used in order to insert a string record around a cursor
       object.

	      bool tcbdbcurput2(BDBCUR *cur, const char *vstr, int cpmode);
		     `cur' specifies the cursor object of writer connection.
		     `vstr' specifies the string of the value.
		     `cpmode' specifies detail adjustment: `BDBCPCURRENT', which means	that  the
		     value  of the current record is overwritten, `BDBCPBEFORE', which means that
		     the new record is inserted before the current  record,  `BDBCPAFTER',  which
		     means that the new record is inserted after the current record.
		     If  successful,  the  return  value  is  true,  else, it is false.  False is
		     returned when the cursor is at invalid position.
		     After insertion, the cursor is moved to the inserted record.

       The function `tcbdbcurout' is used in order to remove the record where a cursor object is.

	      bool tcbdbcurout(BDBCUR *cur);
		     `cur' specifies the cursor object of writer connection.
		     If successful, the return value is  true,	else,  it  is  false.	False  is
		     returned when the cursor is at invalid position.
		     After deletion, the cursor is moved to the next record if possible.

       The  function `tcbdbcurkey' is used in order to get the key of the record where the cursor
       object is.

	      char *tcbdbcurkey(BDBCUR *cur, int *sp);
		     `cur' specifies the cursor object.
		     `sp' specifies the pointer to the variable into which the size of the region
		     of the return value is assigned.
		     If  successful,  the  return  value is the pointer to the region of the key,
		     else, it is `NULL'.  `NULL' is returned when the cursor is at invalid  posi-
		     tion.
		     Because  an additional zero code is appended at the end of the region of the
		     return value, the return  value  can  be  treated	as  a  character  string.
		     Because  the region of the return value is allocated with the `malloc' call,
		     it should be released with the `free' call when it is no longer in use.

       The function `tcbdbcurkey2' is used in order to get the key string of the record where the
       cursor object is.

	      char *tcbdbcurkey2(BDBCUR *cur);
		     `cur' specifies the cursor object.
		     If  successful,  the  return  value  is  the  string of the key, else, it is
		     `NULL'.  `NULL' is returned when the cursor is at invalid position.
		     Because the region of the return value is allocated with the `malloc'  call,
		     it should be released with the `free' call when it is no longer in use.

       The function `tcbdbcurkey3' is used in order to get the key of the record where the cursor
       object is, as a volatile buffer.

	      const char *tcbdbcurkey3(BDBCUR *cur, int *sp);
		     `cur' specifies the cursor object.
		     `sp' specifies the pointer to the variable into which the size of the region
		     of the return value is assigned.
		     If  successful,  the  return  value is the pointer to the region of the key,
		     else, it is `NULL'.  `NULL' is returned when the cursor is at invalid  posi-
		     tion.
		     Because  an additional zero code is appended at the end of the region of the
		     return value, the return  value  can  be  treated	as  a  character  string.
		     Because  the region of the return value is volatile and it may be spoiled by
		     another operation of the database, the data should be  copied  into  another
		     involatile buffer immediately.

       The  function `tcbdbcurval' is used in order to get the value of the record where the cur-
       sor object is.

	      char *tcbdbcurval(BDBCUR *cur, int *sp);
		     `cur' specifies the cursor object.
		     `sp' specifies the pointer to the variable into which the size of the region
		     of the return value is assigned.
		     If  successful,  the return value is the pointer to the region of the value,
		     else, it is `NULL'.  `NULL' is returned when the cursor is at invalid  posi-
		     tion.
		     Because  an additional zero code is appended at the end of the region of the
		     return value, the return  value  can  be  treated	as  a  character  string.
		     Because  the region of the return value is allocated with the `malloc' call,
		     it should be released with the `free' call when it is no longer in use.

       The function `tcbdbcurval2' is used in order to get the value string of the  record  where
       the cursor object is.

	      char *tcbdbcurval2(BDBCUR *cur);
		     `cur' specifies the cursor object.
		     If  successful,  the  return  value  is the string of the value, else, it is
		     `NULL'.  `NULL' is returned when the cursor is at invalid position.
		     Because the region of the return value is allocated with the `malloc'  call,
		     it should be released with the `free' call when it is no longer in use.

       The function `tcbdbcurval3' is used in order to get the value of the record where the cur-
       sor object is, as a volatile buffer.

	      const char *tcbdbcurval3(BDBCUR *cur, int *sp);
		     `cur' specifies the cursor object.
		     `sp' specifies the pointer to the variable into which the size of the region
		     of the return value is assigned.
		     If  successful,  the return value is the pointer to the region of the value,
		     else, it is `NULL'.  `NULL' is returned when the cursor is at invalid  posi-
		     tion.
		     Because  an additional zero code is appended at the end of the region of the
		     return value, the return  value  can  be  treated	as  a  character  string.
		     Because  the region of the return value is volatile and it may be spoiled by
		     another operation of the database, the data should be  copied  into  another
		     involatile buffer immediately.

       The  function  `tcbdbcurrec'  is  used in order to get the key and the value of the record
       where the cursor object is.

	      bool tcbdbcurrec(BDBCUR *cur, TCXSTR *kxstr, TCXSTR *vxstr);
		     `cur' specifies the cursor object.
		     `kxstr' specifies the object into which the key is wrote down.
		     `vxstr' specifies the object into which the value is wrote down.
		     If successful, the return value is  true,	else,  it  is  false.	False  is
		     returned when the cursor is at invalid position.

SEE ALSO
       tcbtest(1), tcbmttest(1), tcbmgr(1), tokyocabinet(3)

Man Page				    2012-08-18					 TCBDB(3)


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