Import BSDDB 4.7.25 (as of svn r89086)

docs_src/db/db_cursor.so

@@ -0,0 +1,76 @@
+m4_comment([$Id: db_cursor.so,v 10.55 2007/10/24 16:06:06 bostic Exp $])
+
+define(M4PAGELOCAL, dbh_cursor)
+include(m4/m4.seealso)
+
+m4_pf_header(m4_ref(dbh_cursor),
+ifelse(M4API, C_API, [dnl
+int
+DB-__GT__cursor(DB *db,
+    DB_TXN *txnid, DBC **cursorp, u_int32_t flags);
+])
+ifelse(M4API, CXX_API, [dnl
+int
+Db::cursor(DbTxn *txnid, Dbc **cursorp, u_int32_t flags);
+]))
+
+m4_p([dnl
+The m4_refT(dbh_cursor) returns a created database cursor.])
+
+m4_p([dnl
+Cursors may span threads, but only serially, that is, the application
+must serialize access to the cursor handle.])
+
+m4_return(dbh_cursor, std)
+
+m4_parambegin
+m4_param_co(cursorp, allocated cursor, REF)
+
+m4_param(flags, [dnl
+m4_sf_or_may
+
+m4_tagbegin
+m4_tag(m4_idef(DB_READ_COMMITTED), [dnl
+Configure a transactional cursor to have degree 2 isolation.  This ensures
+the stability of the current data item read by this cursor but permits data
+read by this cursor to be modified or deleted prior to the commit of the
+transaction for this cursor.])
+
+m4_tag(m4_idef(DB_READ_UNCOMMITTED), [dnl
+Configure a transactional cursor to have degree 1 isolation.  Read
+operations performed by the cursor may return modified but not yet
+committed data.  Silently ignored if the m4_ref(DB_READ_UNCOMMITTED)
+flag was not specified when the underlying database was opened.])
+
+m4_tag(m4_idef(DB_WRITECURSOR), [dnl
+Specify that the cursor will be used to update the database.  The
+underlying database environment must have been opened using the
+m4_ref(DB_INIT_CDB) flag.])
+
+m4_tag(m4_idef(DB_TXN_SNAPSHOT), [dnl
+Configure a transactional cursor to operate with read-only
+m4_link(M4RELDIR/ref/transapp/read, snapshot isolation).  For databases
+with the m4_ref(DB_MULTIVERSION) flag set, data values will be read as
+they are when the cursor is opened, without taking read locks.  This
+flag implicitly begins a transaction that is committed when the cursor
+is closed.  Silently ignored if m4_ref(DB_MULTIVERSION) not set on the
+underlying database or if a transaction is supplied in the m4_arg(txnid)
+parameter.])
+m4_tagend])
+
+m4_param(txnid, [dnl
+Cursor operations are not automatically transaction-protected, even if
+the m4_ref(DB_AUTO_COMMIT) flag is specified to the
+m4_ref(dbenv_set_flags) or m4_refT(dbh_open)s.  If cursor operations are
+to be transaction-protected, the m4_arg(txnid) parameter must be a
+transaction handle returned from m4_ref(txn_begin); otherwise, NULL.  To
+transaction-protect cursor operations, cursors must be opened and closed
+within the context of a transaction, and the m4_arg(txnid) parameter
+specifies the transaction context in which the cursor may be used.])
+
+m4_paramend
+
+m4_err(dbh_cursor, rephandle, replockout, einval)
+
+m4_seealso(Dbc)
+m4_page_footer