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Diffstat (limited to 'lib/libc/db/man/mpool.3')
| -rw-r--r-- | lib/libc/db/man/mpool.3 | 220 |
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diff --git a/lib/libc/db/man/mpool.3 b/lib/libc/db/man/mpool.3 deleted file mode 100644 index e625dc4..0000000 --- a/lib/libc/db/man/mpool.3 +++ /dev/null @@ -1,220 +0,0 @@ -.\" 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. -.\" -.\" @(#)mpool.3 8.1 (Berkeley) 6/4/93 -.\" $Id$ -.\" -.TH MPOOL 3 "June 4, 1993" -.UC 7 -.SH NAME -mpool \- shared memory buffer pool -.SH SYNOPSIS -.nf -.ft B -#include <db.h> -#include <mpool.h> - -MPOOL * -mpool_open (DBT *key, int fd, pgno_t pagesize, pgno_t maxcache); - -void -mpool_filter (MPOOL *mp, void (*pgin)(void *, pgno_t, void *), -.ti +5 -void (*pgout)(void *, pgno_t, void *), void *pgcookie); - -void * -mpool_new (MPOOL *mp, pgno_t *pgnoaddr); - -void * -mpool_get (MPOOL *mp, pgno_t pgno, u_int flags); - -int -mpool_put (MPOOL *mp, void *pgaddr, u_int flags); - -int -mpool_sync (MPOOL *mp); - -int -mpool_close (MPOOL *mp); -.ft R -.fi -.SH DESCRIPTION -.IR Mpool -is the library interface intended to provide page oriented buffer management -of files. -The buffers may be shared between processes. -.PP -The function -.I mpool_open -initializes a memory pool. -The -.I key -argument is the byte string used to negotiate between multiple -processes wishing to share buffers. -If the file buffers are mapped in shared memory, all processes using -the same key will share the buffers. -If -.I key -is NULL, the buffers are mapped into private memory. -The -.I fd -argument is a file descriptor for the underlying file, which must be seekable. -If -.I key -is non-NULL and matches a file already being mapped, the -.I fd -argument is ignored. -.PP -The -.I pagesize -argument is the size, in bytes, of the pages into which the file is broken up. -The -.I maxcache -argument is the maximum number of pages from the underlying file to cache -at any one time. -This value is not relative to the number of processes which share a file's -buffers, but will be the largest value specified by any of the processes -sharing the file. -.PP -The -.I mpool_filter -function is intended to make transparent input and output processing of the -pages possible. -If the -.I pgin -function is specified, it is called each time a buffer is read into the memory -pool from the backing file. -If the -.I pgout -function is specified, it is called each time a buffer is written into the -backing file. -Both functions are called with the -.I pgcookie -pointer, the page number and a pointer to the page to being read or written. -.PP -The function -.I mpool_new -takes an MPOOL pointer and an address as arguments. -If a new page can be allocated, a pointer to the page is returned and -the page number is stored into the -.I pgnoaddr -address. -Otherwise, NULL is returned and errno is set. -.PP -The function -.I mpool_get -takes a MPOOL pointer and a page number as arguments. -If the page exists, a pointer to the page is returned. -Otherwise, NULL is returned and errno is set. -The flags parameter is not currently used. -.PP -The function -.I mpool_put -unpins the page referenced by -.IR pgaddr . -.I Pgaddr -must be an address previously returned by -.I mpool_get -or -.IR mpool_new . -The flag value is specified by -.IR or 'ing -any of the following values: -.TP -MPOOL_DIRTY -The page has been modified and needs to be written to the backing file. -.PP -.I Mpool_put -returns 0 on success and -1 if an error occurs. -.PP -The function -.I mpool_sync -writes all modified pages associated with the MPOOL pointer to the -backing file. -.I Mpool_sync -returns 0 on success and -1 if an error occurs. -.PP -The -.I mpool_close -function free's up any allocated memory associated with the memory pool -cookie. -Modified pages are -.B not -written to the backing file. -.I Mpool_close -returns 0 on success and -1 if an error occurs. -.SH ERRORS -The -.I mpool_open -function may fail and set -.I errno -for any of the errors specified for the library routine -.IR malloc (3). -.PP -The -.I mpool_get -function may fail and set -.I errno -for the following: -.TP 15 -[EINVAL] -The requested record doesn't exist. -.PP -The -.I mpool_new -and -.I mpool_get -functions may fail and set -.I errno -for any of the errors specified for the library routines -.IR read (2) , -.IR write (2) , -and -.IR malloc (3). -.PP -The -.I mpool_sync -function may fail and set -.I errno -for any of the errors specified for the library routine -.IR write (2). -.PP -The -.I mpool_close -function may fail and set -.I errno -for any of the errors specified for the library routine -.IR free (3). -.SH "SEE ALSO" -.IR dbopen (3), -.IR btree (3), -.IR hash (3), -.IR recno (3) |
