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-rw-r--r--man3/btree.326
1 files changed, 13 insertions, 13 deletions
diff --git a/man3/btree.3 b/man3/btree.3
index dfa8f4e..e93e25b 100644
--- a/man3/btree.3
+++ b/man3/btree.3
@@ -5,7 +5,7 @@
.\"
.\" @(#)btree.3 8.4 (Berkeley) 8/18/94
.\"
-.TH btree 3 2022-12-04 "Linux man-pages 6.05.01"
+.TH btree 3 2023-10-31 "Linux man-pages 6.7"
.\".UC 7
.SH NAME
btree \- btree database access method
@@ -26,7 +26,7 @@ Since glibc 2.2, glibc no longer provides these interfaces.
Probably, you are looking for the APIs provided by the
.I libdb
library instead.
-.PP
+.P
The routine
.BR dbopen (3)
is the library interface to database files.
@@ -34,16 +34,16 @@ One of the supported file formats is btree files.
The general description of the database access methods is in
.BR dbopen (3),
this manual page describes only the btree-specific information.
-.PP
+.P
The btree data structure is a sorted, balanced tree structure storing
associated key/data pairs.
-.PP
+.P
The btree access-method-specific data structure provided to
.BR dbopen (3)
is defined in the
.I <db.h>
include file as follows:
-.PP
+.P
.in +4n
.EX
typedef struct {
@@ -58,7 +58,7 @@ typedef struct {
} BTREEINFO;
.EE
.in
-.PP
+.P
The elements of this structure are as follows:
.TP
.I flags
@@ -178,7 +178,7 @@ big endian order would be the number 4,321.
If
.I lorder
is 0 (no order is specified), the current host order is used.
-.PP
+.P
If the file already exists (and the
.B O_TRUNC
flag is not specified), the
@@ -189,15 +189,15 @@ and
.I psize
are ignored
in favor of the values used when the tree was created.
-.PP
+.P
Forward sequential scans of a tree are from the least key to the greatest.
-.PP
+.P
Space freed up by deleting key/data pairs from the tree is never reclaimed,
although it is normally made available for reuse.
This means that the btree storage structure is grow-only.
The only solutions are to avoid excessive deletions, or to create a fresh
tree periodically from a scan of an existing one.
-.PP
+.P
Searches, insertions, and deletions in a btree will all complete in
O lg base N where base is the average fill factor.
Often, inserting ordered data into btrees results in a low fill factor.
@@ -217,13 +217,13 @@ Only big and little endian byte order is supported.
.BR hash (3),
.BR mpool (3),
.BR recno (3)
-.PP
+.P
.IR "The Ubiquitous B-tree" ,
Douglas Comer, ACM Comput. Surv. 11, 2 (June 1979), 121-138.
-.PP
+.P
.IR "Prefix B-trees" ,
Bayer and Unterauer, ACM Transactions on Database Systems, Vol. 2, 1
(March 1977), 11-26.
-.PP
+.P
.IR "The Art of Computer Programming Vol. 3: Sorting and Searching" ,
D.E. Knuth, 1968, pp 471-480.