1 .\" Copyright (c) 1990, 1993
2 .\" The Regents of the University of California. All rights reserved.
4 .\" Redistribution and use in source and binary forms, with or without
5 .\" modification, are permitted provided that the following conditions
7 .\" 1. Redistributions of source code must retain the above copyright
8 .\" notice, this list of conditions and the following disclaimer.
9 .\" 2. Redistributions in binary form must reproduce the above copyright
10 .\" notice, this list of conditions and the following disclaimer in the
11 .\" documentation and/or other materials provided with the distribution.
12 .\" 3. All advertising materials mentioning features or use of this software
13 .\" must display the following acknowledgement:
14 .\" This product includes software developed by the University of
15 .\" California, Berkeley and its contributors.
16 .\" 4. Neither the name of the University nor the names of its contributors
17 .\" may be used to endorse or promote products derived from this software
18 .\" without specific prior written permission.
20 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 .\" @(#)recno.3 8.5 (Berkeley) 8/18/94
34 .TH RECNO 3 2012-04-23 "" "Linux Programmer's Manual"
37 recno \- record number database access method
41 #include <sys/types.h>
47 This page documents interfaces provided in glibc up until version 2.1.
48 Since version 2.2, glibc no longer provides these interfaces.
49 Probably, you are looking for the APIs provided by the
55 is the library interface to database files.
56 One of the supported file formats is record number files.
57 The general description of the database access methods is in
59 this manual page describes only the recno specific information.
61 The record number data structure is either variable or fixed-length
62 records stored in a flat-file format, accessed by the logical record
64 The existence of record number five implies the existence of records
65 one through four, and the deletion of record number one causes
66 record number five to be renumbered to record number four, as well
67 as the cursor, if positioned after record number one, to shift down
70 The recno access method specific data structure provided to
74 include file as follows:
80 unsigned int cachesize;
90 The elements of this structure are defined as follows:
93 The flag value is specified by ORing
94 any of the following values:
98 The records are fixed-length, not byte delimited.
101 specifies the length of the record, and the structure element
103 is used as the pad character.
104 Any records, inserted into the database, that are less than
106 bytes long are automatically padded.
109 In the interface specified by
111 the sequential record retrieval fills in both the caller's key and
115 flag is specified, the
117 routines are not required to fill in the key structure.
118 This permits applications to retrieve records at the end of files without
119 reading all of the intervening records.
122 This flag requires that a snapshot of the file be taken when
124 is called, instead of permitting any unmodified records to be read from
129 A suggested maximum size, in bytes, of the memory cache.
132 advisory, and the access method will allocate more memory rather than fail.
135 is 0 (no size is specified) a default cache is used.
138 The recno access method stores the in-memory copies of its records
140 This value is the size (in bytes) of the pages used for nodes in that tree.
143 is 0 (no page size is specified) a page size is chosen based on the
144 underlying file system I/O block size.
147 for more information.
150 The byte order for integers in the stored database metadata.
151 The number should represent the order as an integer; for example,
152 big endian order would be the number 4,321.
155 is 0 (no order is specified) the current host order is used.
158 The length of a fixed-length record.
161 The delimiting byte to be used to mark the end of a record for
162 variable-length records, and the pad character for fixed-length
164 If no value is specified, newlines ("\en") are used to mark the end
165 of variable-length records and fixed-length records are padded with
169 The recno access method stores the in-memory copies of its records
173 is non-NULL, it specifies the name of the btree file,
174 as if specified as the filename for a
178 The data part of the key/data pair used by the
181 is the same as other access methods.
182 The key is different.
185 field of the key should be a pointer to a memory location of type
190 This type is normally the largest unsigned integral type available to
194 field of the key should be the size of that type.
196 Because there can be no metadata associated with the underlying
197 recno access method files, any changes made to the default values
198 (e.g., fixed record length or byte separator value) must be explicitly
199 specified each time the file is opened.
201 In the interface specified by
205 interface to create a new record will cause the creation of multiple,
206 empty records if the record number is more than one greater than the
207 largest record currently in the database.
211 access method routines may fail and set
213 for any of the errors specified for the library routine
218 An attempt was made to add a record to a fixed-length database that
219 was too large to fit.
221 Only big and little endian byte order is supported.
228 .IR "Document Processing in a Relational Database System" ,
229 Michael Stonebraker, Heidi Stettner, Joseph Kalash, Antonin Guttman,
230 Nadene Lynn, Memorandum No. UCB/ERL M82/32, May 1982.