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diff --git a/bdb/docs/api_c/dbm.html b/bdb/docs/api_c/dbm.html deleted file mode 100644 index 783d59e6271..00000000000 --- a/bdb/docs/api_c/dbm.html +++ /dev/null @@ -1,220 +0,0 @@ -<!--$Id: dbm.so,v 10.18 2000/03/01 21:41:29 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB: dbm/ndbm</title> -<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> -<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> -</head> -<body bgcolor=white> - <a name="2"><!--meow--></a> -<table><tr valign=top> -<td> -<h1>dbm/ndbm</h1> -</td> -<td width="1%"> -<a href="../api_c/c_index.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> -</td></tr></table> -<hr size=1 noshade> -<tt> -<h3><pre> -#define DB_DBM_HSEARCH 1 -#include <db.h> -<p> -typedef struct { - char *dptr; - int dsize; -} datum; -<hr size=1 noshade> -<h3>Dbm Functions</h3> -int -dbminit(char *file); -<p> -int -dbmclose(); -<p> -datum -fetch(datum key); -<p> -int -store(datum key, datum content); -<p> -int -delete(datum key); -<p> -datum -firstkey(void); -<p> -datum -nextkey(datum key); -<hr size=1 noshade> -<h3>Ndbm Functions</h3> -DBM * -dbm_open(char *file, int flags, int mode); -<p> -void -dbm_close(DBM *db); -<p> -datum -dbm_fetch(DBM *db, datum key); -<p> -int -dbm_store(DBM *db, datum key, datum content, int flags); -<p> -int -dbm_delete(DBM *db, datum key); -<p> -datum -dbm_firstkey(DBM *db); -<p> -datum -dbm_nextkey(DBM *db); -<p> -int -dbm_error(DBM *db); -<p> -int -dbm_clearerr(DBM *db); -</pre></h3> -<h1>Description</h1> -<p>The dbm interfaces to the Berkeley DB library are intended to provide -high-performance implementations and source code compatibility for -applications written to historic interfaces. They are not recommended -for any other purpose. The historic dbm database format -<b>is not supported</b>, and databases previously built using the real -dbm libraries cannot be read by the Berkeley DB functions. -<p>To compile dbm applications, replace the application's -<b>#include</b> of the dbm or ndbm include file (e.g., -<b>#include <dbm.h></b> or <b>#include <ndbm.h></b>) -with the following two lines: -<p><blockquote><pre>#define DB_DBM_HSEARCH 1 -#include <db.h></pre></blockquote> -<p>and recompile. If the application attempts to load against a dbm library -(e.g., <b>-ldbm</b>), remove the library from the load line. -<p><b>Key</b> and <b>content</b> arguments are objects described by the -<b>datum</b> typedef. A <b>datum</b> specifies a string of -<b>dsize</b> bytes pointed to by <b>dptr</b>. Arbitrary binary data, -as well as normal text strings, is allowed. -<h3>Dbm Functions</h3> -<p>Before a database can be accessed, it must be opened by dbminit. -This will open and/or create the database <b>file</b>.db. If created, -the database file is created read/write by owner only (as described in -<b>chmod</b>(2) and modified by the process' umask value at the time -of creation (see <b>umask</b>(2)). The group ownership of created -files is based on the system and directory defaults, and is not further -specified by Berkeley DB. -<p>A database may be closed, and any held resources released, by calling -dbmclose. -<p>Once open, the data stored under a key is accessed by fetch and -data is placed under a key by store. A key (and its associated -contents) is deleted by delete. A linear pass through all keys -in a database may be made, in an (apparently) random order, by use of -firstkey and nextkey. The firstkey function will return -the first key in the database. The nextkey function will return the next -key in the database. -<p>The following code will traverse the data base: -<p><blockquote><pre>for (key = firstkey(); - key.dptr != NULL; key = nextkey(key)) { - ... -}</pre></blockquote> -<h3>Ndbm Functions</h3> -<p>Before a database can be accessed, it must be opened by dbm_open. -This will open and/or create the database file <b>file.db</b> depending -on the flags parameter (see <b>open</b>(2)). If created, the database -file is created with mode <b>mode</b> (as described in <b>chmod</b>(2)) and modified by the process' umask value at the time of creation (see -<b>umask</b>(2)). The group ownership of created files is based on -the system and directory defaults, and is not further specified by -Berkeley DB. -<p>Once open, the data stored under a key is accessed by dbm_fetch -and data is placed under a key by dbm_store. The <b>flags</b> -field can be either <b>DBM_INSERT</b> or <b>DBM_REPLACE</b>. -<b>DBM_INSERT</b> will only insert new entries into the database and will -not change an existing entry with the same key. <b>DBM_REPLACE</b> will -replace an existing entry if it has the same key. A key (and its -associated contents) is deleted by dbm_delete. A linear pass -through all keys in a database may be made, in an (apparently) random -order, by use of dbm_firstkey and dbm_nextkey. The -dbm_firstkey function will return the first key in the database. The -dbm_nextkey function will return the next key in the database. -<p>The following code will traverse the data base: -<p><blockquote><pre>for (key = dbm_firstkey(db); - key.dptr != NULL; key = dbm_nextkey(db)) { - ... -}</pre></blockquote> -<h3>Compatibility Notes</h3> -<p>The historic dbm library created two underlying database files, -traditionally named <b>file.dir</b> and <b>file.pag</b>. The Berkeley DB -library creates a single database file named <b>file.db</b>. -Applications that are aware of the underlying database file names may -require additional source code modifications. -<p>The historic dbminit interface required that the underlying -<b>.dir</b> and <b>.pag</b> files already exist (empty databases were -created by first manually creating zero-length <b>.dir</b> and -<b>.pag</b> files). Applications that expect to create databases using -this method may require additional source code modifications. -<p>The historic dbm_dirfno and dbm_pagfno macros are -supported, but will return identical file descriptors as there is only a -single underlying file used by the Berkeley DB hashing access method. -Applications using both file descriptors for locking may require -additional source code modifications. -<p>If applications using the dbm interface exits without first -closing the database, it may lose updates because the Berkeley DB library -buffers writes to underlying databases. Such applications will require -additional source code modifications to work correctly with the Berkeley DB -library. -<h3>Dbm Diagnostics</h3> -<p>The dbminit function returns -1 on failure, setting <b>errno</b>, -and 0 on success. -<p>The fetch function sets the <b>dptr</b> field of the returned -<b>datum</b> to NULL on failure, setting <b>errno</b>, -and returns a non-NULL <b>dptr</b> on success. -<p>The store function returns -1 on failure, setting <b>errno</b>, -and 0 on success. -<p>The delete function returns -1 on failure, setting <b>errno</b>, -and 0 on success. -<p>The firstkey function sets the <b>dptr</b> field of the returned -<b>datum</b> to NULL on failure, setting <b>errno</b>, -and returns a non-NULL <b>dptr</b> on success. -<p>The nextkey function sets the <b>dptr</b> field of the returned -<b>datum</b> to NULL on failure, setting <b>errno</b>, -and returns a non-NULL <b>dptr</b> on success. -<h1>Errors</h1> -<p>The dbminit, fetch, store, delete, firstkey and nextkey functions may fail -and return a non-zero error for errors specified for other Berkeley DB and C -library or system functions. -<h3>Ndbm Diagnostics</h3> -<p>The dbm_close function returns non-zero when an error has occurred reading or -writing the database. -<p>The dbm_close function resets the error condition on the named database. -<p>The dbm_open function returns NULL on failure, setting <b>errno</b>, -and 0 on success. -<p>The dbm_fetch function sets the <b>dptr</b> field of the returned -<b>datum</b> to NULL on failure, setting <b>errno</b>, -and returns a non-NULL <b>dptr</b> on success. -<p>The dbm_store function returns -1 on failure, setting <b>errno</b>, -0 on success, and 1 if DBM_INSERT was set and the specified key already -existed in the database. -<p>The dbm_delete function returns -1 on failure, setting <b>errno</b>, -and 0 on success. -<p>The dbm_firstkey function sets the <b>dptr</b> field of the returned -<b>datum</b> to NULL on failure, setting <b>errno</b>, -and returns a non-NULL <b>dptr</b> on success. -<p>The dbm_nextkey function sets the <b>dptr</b> field of the returned -<b>datum</b> to NULL on failure, setting <b>errno</b>, -and returns a non-NULL <b>dptr</b> on success. -<p>The dbm_close function returns -1 on failure, setting <b>errno</b>, -and 0 on success. -<p>The dbm_close function returns -1 on failure, setting <b>errno</b>, -and 0 on success. -<h1>Errors</h1> -<p>The dbm_open, dbm_close, dbm_fetch, dbm_store, dbm_delete, dbm_firstkey -and dbm_nextkey functions may fail and return a non-zero error for errors -specified for other Berkeley DB and C library or system functions. -</tt> -<table><tr><td><br></td><td width="1%"> -<a href="../api_c/c_index.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |