.\" Copyright (c) 1990, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"	@(#)dbopen.3	8.5 (Berkeley) 1/2/94
.\"
.\" Japanese Version Copyright (c) 1999 Shouichi Saito
.\"	all rights reserved.
.\" Translated Thu Jul 22 00:00:00 JST 1999
.\"	by Shouichi Saito <ss236rx@ymg.urban.ne.jp>
.\" Proofed Tue Aug 19 1999 by NAKANO Takeo <nakano@apm.seikei.ac.jp>
.\"
.\"WORD:	descriptor	ǥץ
.TH DBOPEN 3 1994-01-02 "" "Linux Programmer's Manual"
.UC 7
.SH ̾
dbopen \- ǡ١᥽å
.SH 
.nf
.B #include <sys/types.h>
.B #include <limits.h>
.B #include <db.h>

.BI "DB *dbopen(const char *" file ", int " flags ", int " mode \
", DBTYPE " type ,
.BI "           const void *" openinfo );
.fi
.SH 
.BR dbopen ()
ϥǡ١եФ饤֥ꥤ󥿡եǤ롣
ݡȤƤեեޥåȤ btree, hash,
UNIX ե˻ظեޥå,  3 ĤǤ롣
btree եޥåȤϡȤ줿Х󥹥ĥ꡼¤Ǥ롣
hashed եޥåȤϡĥǽưŪ hash Ǥ롣
եåȥե (flat-file) եޥåȤϡ
Ĺ/ĹΥ쥳ɤʤХȥȥ꡼եǤ롣
줾ΥեޥåȤȡեեޥåȤͭξ
줾бޥ˥奢ڡ
.BR btree (3),
.BR hash (3),
.BR recno (3)
˾ܺ٤˵ҤƤ롣
.PP
.BR dbopen ()

.I file
ɤ߹ (ɤ߽) 뤿˥ץ󤹤롣
file ѥ᡼ NULL ˤС
ǥ¸ʤե뤳ȤǤ롣
.PP
.I flags

.I mode

.BR open (2)
롼ǻꤹΤƱͤǤ롣
̣ĥե饰
.BR O_CREAT ,
.BR O_EXCL ,
.BR O_EXLOCK ,
.BR O_NONBLOCK ,
.BR O_RDONLY ,
.BR O_RDWR ,
.BR O_SHLOCK ,
.B O_TRUNC
Ǥ롣
(:
.B O_WRONLY
ǥǡ١ե򳫤Ͻʤ)
.\"Three additional options may be specified by
.\".IR or 'ing
.\"them into the
.\".I flags
.\"argument.
.\".TP
.\"DB_LOCK
.\"Do the necessary locking in the database to support concurrent access.
.\"If concurrent access isn't needed or the database is read-only this
.\"flag should not be set, as it tends to have an associated performance
.\"penalty.
.\".TP
.\"DB_SHMEM
.\"Place the underlying memory pool used by the database in shared
.\"memory.
.\"Necessary for concurrent access.
.\".TP
.\"DB_TXN
.\"Support transactions in the database.
.\"The DB_LOCK and DB_SHMEM flags must be set as well.
.PP
.I type

.I DBTYPE
Ǥ (󥯥롼ɥե
.I <db.h>
Ƥ)
.BR DB_BTREE ,
.BR DB_HASH ,
.B DB_RECNO
Τ줫򥻥åȤǤ롣
.PP
.I openinfo
ϥ᥽åɤ˸ͭʹ¤ΤؤΥݥ󥿤Ǥ롣
줾ι¤Τ˴ؤƤϳƥ᥽åɤ
ޥ˥奢ڡ˵ҤƤ롣
.I openinfo
 NULL ξ硢줾Υ᥽åɤȥƥȤŬ礷
ǥեȤѤ롣
.PP
.BR dbopen ()
ϡ
.I DB
¤ΤؤΥݥ󥿤򡢥顼ξ NULL ֤
.I DB
¤Τ
.I <db.h>
󥯥롼ɥեƤꡢ
ʤȤʲΤ褦ʥեɤäƤ롣
.sp
.in +4n
.nf
typedef struct {
    DBTYPE type;
    int (*close)(const DB *db);
    int (*del)(const DB *db, const DBT *key, unsigned int flags);
    int (*fd)(const DB *db);
    int (*get)(const DB *db, DBT *key, DBT *data, unsigned int flags);
    int (*put)(const DB *db, DBT *key, const DBT *data,
               unsigned int flags);
    int (*sync)(const DB *db, unsigned int flags);
    int (*seq)(const DB *db, DBT *key, DBT *data, unsigned int flags);
} DB;
.fi
.in
.PP
Ǥˤϡǡ١Υפȡ
͡ư򤹤ؿΥåȤҤƤ롣
δؿ
.BR dbopen ()
ˤä֤빽¤ΤؤΥݥ󥿤ˤȤ롣
/ǡ¤ΤؤΥݥ󥿤ե饰ͤΤ⤢롣
.TP
.I type
ѤƤ륢᥽å (ȥեեޥå) η
.TP
.I close
å夵줿ǥݤΥ롼ؤΥݥ󥿡
Ƥ줿꥽Ѥե()򥯥롣
/ǡФ˥å夵Ƥ硢
.I close

.I sync
ؿǤƱ˼Ԥȡ̷⤬뤫򼺤ǽ롣
.I close
롼ϥ顼ξ \-1 ֤
.RI ( errno
򥻥åȤ) 0 ֤
.TP
.I del
ǡ١饭/ǡФ롼ؤΥݥ󥿡
.IP
.I flag
ϼͤåȤǤ롣
.RS
.TP
.B R_CURSOR
 (cursor) ȤƤ쥳ɤ롣
äƽƤʤƤϤʤʤ
.RE
.IP
.I delete
롼ϥ顼ξ \-1 ֤
.RI ( errno
򥻥åȤ) 0 ֤ޤ
.I key
ե̵ 1 ֤
.TP
.I fd
ѤƤǡ١Υեǥץ֤롼
ؤΥݥ󥿡
Ʊե̾
.I file

.BR dbopen ()
ƤӽФƤΥץФơ
Υե򼨤ñΥեǥץ֤롣
Υեǥץϥåؿ
.BR fcntl (2)

.BR flock (2)
ؤΰȤư˻ѤǤ롣
Υեǥץϡɬ⥢᥽åɤ
ѤƤեΤ줫˴ϢŤƤʤƤɤ
Υǡ١ˤϥեǥץ̵
.I fd
롼ϥ顼ξ \-1 ֤
.RI ( errno
򥻥åȤ)ȥեǥץ֤
.TP
.I get
ǡ١饭ѤƥǡФ
롼ؤΥݥ󥿡
ꤷ
.I key
˴ϢŤ줿ǡΥɥ쥹Ĺ
.I data
Ȥ빽¤Τ֤롣
.I get
롼ϥ顼ξ \-1 ֤
.RI ( errno
򥻥åȤ) 0 ֤ޤ
.I key
ե̵ 1 ֤
.TP
.I put
/ǡФǡ١Ǽ롼ؤΥݥ󥿡
.IP
.I flag
ˤϼͤΤΤɤ줫ĤåȤǤ롣
.RS
.TP
.B R_CURSOR
뤬ȤƤ륭/ǡФ֤롣
äƽƤɬפ롣
.TP
.B R_IAFTER
.I key
ǻȤǡľˡ
/ǡФäƥǡɲä롣
ɲä줿/ǡФΥ쥳ֹ
.I key
¤Τ֤롣
.RB ( DB_RECNO
ˡǤΤ߻Ȥ롣)
.TP
.B R_IBEFORE
.I key
ǻȤǡľˡ
/ǡФäƥǡ롣
ɲä줿/ǡФΥ쥳ֹ
.I key
¤Τ֤롣
.RB ( DB_RECNO
᥽åɤǤΤ߻Ȥ롣)
.TP
.B R_NOOVERWRITE
餫¸ߤʤ˸¤ꡢ/ǡФ򤤤롣
.TP
.B R_SETCURSOR
/ǡФǼᡢؤ褦˥֤򥻥åȤ뤤Ͻ
롣
.RB ( DB_BTREE

.B DB_RECNO
᥽åɤǤΤ߻Ȥ롣)
.RE
.IP
.B R_SETCURSOR

.B DB_BTREE

.B DB_RECNO
᥽åɤǤѤǤʤ
ʤʤ
.B R_SETCURSOR
Ѥˤϡѹ̵ͭν򥭡
äƤʤФʤʤǤ롣
.IP
.B R_IAFTER

.B R_IBEFORE

.B DB_RECNO
᥽åɤǤѤǤʤ
¸ˤϡ᥽åɤ
ʤФʤʤǤ롣
줬ΩΤϡ㤨СŤ餿Ωʥ쥳ֹ椬
ˤʤäƤ褦ʾǤ롣
.IP
.I put
롼ΥǥեȤưϡ/ǡФ
¸ߤ륭֤ƳǼưǤ롣
.IP
.I put
롼ϥ顼ξ \-1 ֤
.RI ( errno
򥻥åȤ) 0 ֤ޤ
.I flag

.B R_NOOVERWRITE
åȤƤƥ¸ߤ 1 ֤
.TP
.I seq
ǡ١饷󥷥˥ǡФ
롼ؤΥݥ󥿡
Υɥ쥹Ĺ
.I key
Ȥ빽¤Τ֤롣ǡΥɥ쥹Ĺ
.I data
Ȥ빽¤Τ֤롣
.IP
󥷥ʥ/ǡФμϤĤǤԤ롣ޤ
֥פΰ֤
.IR del ,
.IR get ,
.IR put ,
.I sync
롼θƤӽФˤϱƶʤ
󥷥ʥ˹Ԥ줿ǡ١ؤѹ
ȿǤ롣ʤθ줿쥳ɤ
֤ʤ줿쥳ɤ֤롣
.IP
ե饰ͤˤ\fBɬ\fPʲ˼
ɤ줫Ĥ򥻥åȤʤФʤʤ
.RS
.TP
.B R_CURSOR
ꤷ˴ϢŤ줿ǡ֤롣
.I get
롼Ȥΰ㤤ϡ뤬ΰ֤˥åȤ뤤
Ǥ롣
(:
.B DB_BTREE
ˡǤϡ֤줿
ɬꤷޥåʤ⤷ʤ
֤줿ϡꤵ줿礭ΤΤ
ǾΤΤˤʤ
(ʬޥåϰϸĤƤ))
.TP
.B R_FIRST
ǡ١κǽΥ/ǡФ֤롣
Ϥ򻲾Ȥ褦˥åȤޤϽ롣
.TP
.B R_LAST
ǡ١κǸΥ/ǡФ֤롣Ϥ򻲾Ȥ
褦˥åȤޤϽ롣
.RB ( DB_BTREE

.B DB_RECNO
᥽åɤǻȤ롣)
.TP
.B R_NEXT
ľΥ/ǡФ롣
뤬åȤƤʤ
.B R_FIRST
ե饰Ʊ
.TP
.B R_PREV
ľΥ/ǡФ롣
뤬åȤƤʤ
.B R_LAST
ե饰Ʊ
.RB ( DB_BTREE

.B DB_RECNO
᥽åɤǻȤ롣)
.RE
.IP
.B R_LAST

.B R_PREV
ϡ
.B DB_BTREE

.B DB_RECNO
ˡǤȤʤ
ʤʤ
.B R_SETCURSOR
Ѥˤϡѹ̵ͭν򥭡äƤʤФʤʤǤ롣
.IP
.I seq
롼ϥ顼ξ \-1 ֤
.RI ( errno
򥻥åȤ)
ξ 0 ֤
ꤷ䥫ȥ礭//ǡФʤ
1 ֤
.B DB_RECNO
᥽åɤȤäƤơ
ĥǡ١ե뤬ʸΥڥեǡ
Ƥ륭/ǡФ̵ˤϡ
.I seq
롼 2 ֤
.TP
.I sync
å夵줿ǥݤФ롼ؤΥݥ󥿡
ǡ١ˤ硢
.I sync
롼ϲθ̤ʤ롣
.IP
flag ˤϰʲͤåȤǤ롣
.RS
.TP
.B R_RECNOSYNC
.B DB_RECNO
᥽åɤȤäƤ
Υե饰򥻥åȤȡ
recno ե뤽ΤΤˤǤϤʤ
Υ١ˤʤäƤ btree ե sync Ԥ롣
(ܺ٤
.BR recno (3)
ޥ˥奢ڡ
.I bfname
եɤƤʬ򻲾ȤΤȡ)
.RE
.IP
.I sync
롼ϥ顼ξ \-1 ֤
.RI ( errno
򥻥åȤ) 0 ֤
.SS /ǡ
ƤΥե륿פˤơ
/ǡФ١ˤƥԤ롣
ȥǡΤ⡢Υǡ¤ǵҤ롣
.in +4n
.nf

typedef struct {
    void  *data;
    size_t size;
} DBT;
.fi
.in
.I DBT
¤ΤγǤϼΤ褦Ƥ롣
.TP
.I data
ХʸؤΥݥ󥿡
.TP
.I size
ХʸĹ
.PP
ȥǡΥХʸϡ
Ūˤ̵¤Ĺʸ򻲾ȤǤ뤬
Ѳǽʥ˼ޤäƤʤƤϤʤʤ
᥽åɤϥХʸΥ饤ȤˤĤƤ
ݾڤƤʤդ뤳ȡ
.SH 顼
.BR dbopen ()
롼ϼԤȥ饤֥롼
.BR open (2)

.BR malloc (3)
ǻꤵƤ륨顼˱
.I errno
򥻥åȤ롣뤤ϰʲ򥻥åȤ롣
.TP
.B [EFTYPE]
ե뤬եޥåȤƤʤ
.TP
.B [EINVAL]
ꤷѥ᡼(ϥåؿХʤ)ߤΥեͤ
äƤʤѥ᡼ؿˤȤạ̵̈
(㤨Ф餫ʤǥȤȤ)
եȥեȥΥС󤬹äƤʤ
.PP
.I close
롼ϼԤȥ饤֥롼
.BR close (2),
.BR read (2),
.BR write (2),
.BR free (3),
.BR fsync (2)
ǻꤵƤ륨顼˱
.I errno
򥻥åȤ롣
.PP
.IR del ,
.IR get ,
.I put

.I seq
롼ϼԤȥ饤֥롼
.BR read (2),
.BR write (2),
.BR free (3),
.BR malloc (3)
ǻꤵƤ륨顼˱
.I errno
򥻥åȤ롣
.PP
.I fd
롼ϥǡ١ФԤ
.I errno

.B ENOENT
򥻥åȤ롣
.PP
.I sync
롼ϼԤȥ饤֥롼
.BR fsync (2)
ǻꤵƤ륨顼˱
.I errno
򥻥åȤ롣
.SH Х
typedef
.I DBT
 ``data base thang''άǤ뤬줬ȤƤΤϡ
ޤȤƤʤ̾פդʤäǤ롣
.PP
եǥץȤäȤϤҤɤʪǤꡢ
ΥСǤϺ
.PP
ɤΥ᥽åɤ⡢Ʊåȥ󥶥
λȤߤƤʤ
.SH Ϣ
.BR btree (3),
.BR hash (3),
.BR mpool (3),
.BR recno (3)
.sp
.IR "LIBTP: Portable, Modular Transactions for UNIX" ,
Margo Seltzer, Michael Olson, USENIX proceedings, Winter 1992.