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diff --git a/man3/mpool.3 b/man3/mpool.3 deleted file mode 100644 index 38f1366..0000000 --- a/man3/mpool.3 +++ /dev/null @@ -1,205 +0,0 @@ -.\" Copyright (c) 1990, 1993 -.\" The Regents of the University of California. All rights reserved. -.\" -.\" SPDX-License-Identifier: BSD-4-Clause-UC -.\" -.\" @(#)mpool.3 8.1 (Berkeley) 6/4/93 -.\" -.TH mpool 3 2023-10-31 "Linux man-pages 6.7" -.UC 7 -.SH NAME -mpool \- shared memory buffer pool -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <db.h> -.B #include <mpool.h> -.P -.BI "MPOOL *mpool_open(DBT *" key ", int " fd ", pgno_t " pagesize \ -", pgno_t " maxcache ); -.P -.BI "void mpool_filter(MPOOL *" mp ", void (*pgin)(void *, pgno_t, void *)," -.BI " void (*" pgout ")(void *, pgno_t, void *)," -.BI " void *" pgcookie ); -.P -.BI "void *mpool_new(MPOOL *" mp ", pgno_t *" pgnoaddr ); -.BI "void *mpool_get(MPOOL *" mp ", pgno_t " pgno ", unsigned int " flags ); -.BI "int mpool_put(MPOOL *" mp ", void *" pgaddr ", unsigned int " flags ); -.P -.BI "int mpool_sync(MPOOL *" mp ); -.BI "int mpool_close(MPOOL *" mp ); -.fi -.SH DESCRIPTION -.IR "Note well" : -This page documents interfaces provided up until glibc 2.1. -Since glibc 2.2, glibc no longer provides these interfaces. -Probably, you are looking for the APIs provided by the -.I libdb -library instead. -.P -.I Mpool -is the library interface intended to provide page oriented buffer management -of files. -The buffers may be shared between processes. -.P -The function -.BR 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. -.P -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. -.P -The -.BR 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. -.P -The function -.BR mpool_new () -takes an -.I 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 -.I errno -is set. -.P -The function -.BR mpool_get () -takes an -.I MPOOL -pointer and a page number as arguments. -If the page exists, a pointer to the page is returned. -Otherwise, NULL is returned and -.I errno -is set. -The -.I flags -argument is not currently used. -.P -The function -.BR mpool_put () -unpins the page referenced by -.IR pgaddr . -.I pgaddr -must be an address previously returned by -.BR mpool_get () -or -.BR mpool_new (). -The flag value is specified by ORing -any of the following values: -.TP -.B MPOOL_DIRTY -The page has been modified and needs to be written to the backing file. -.P -.BR mpool_put () -returns 0 on success and \-1 if an error occurs. -.P -The function -.BR mpool_sync () -writes all modified pages associated with the -.I MPOOL -pointer to the -backing file. -.BR mpool_sync () -returns 0 on success and \-1 if an error occurs. -.P -The -.BR 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. -.BR mpool_close () -returns 0 on success and \-1 if an error occurs. -.SH ERRORS -The -.BR mpool_open () -function may fail and set -.I errno -for any of the errors specified for the library routine -.BR malloc (3). -.P -The -.BR mpool_get () -function may fail and set -.I errno -for the following: -.TP 15 -.B EINVAL -The requested record doesn't exist. -.P -The -.BR mpool_new () -and -.BR mpool_get () -functions may fail and set -.I errno -for any of the errors specified for the library routines -.BR read (2), -.BR write (2), -and -.BR malloc (3). -.P -The -.BR mpool_sync () -function may fail and set -.I errno -for any of the errors specified for the library routine -.BR write (2). -.P -The -.BR mpool_close () -function may fail and set -.I errno -for any of the errors specified for the library routine -.BR free (3). -.SH STANDARDS -BSD. -.SH SEE ALSO -.BR btree (3), -.BR dbopen (3), -.BR hash (3), -.BR recno (3) |