dba_open
(PHP 3>= 3.0.8, PHP 4 )
dba_open -- Open database
Description
resource dba_open ( string path, string mode, string handler
[, ...])
dba_open() establishes a database instance for path with
mode using handler.
path is commonly a regular path in your filesystem.
mode is "r" for read access, "w" for
read/write access to an already existing database, "c"
for read/write access and database creation if it doesn't
currently exist, and "n" for create, truncate
and read/write access. Additional you can set the database
lock method with the next char. Use "l" to lock
the database with an .lck file or "d" to lock
the databasefile itself. It is important that all of your
applications do this consistently. If you want to test the
access and do not want to wait for the lock you can add
"t" as third character. When you are absolutely
sure that you do not require database locking you can do
so by using "-" instead of "l" or "d".
When none of "d", "l" or "-"
is used dba will lock on the database file as it would with
"d".
handler is the name of the handler which shall be used
for accessing path. It is passed all optional parameters
given to dba_open() and can act on behalf of them.
dba_open() returns a positive handle or FALSE, in the case
the database was opened successfull or fails, respectively.
Note: There can only be one writer for one database file.
When you use dba on a webserver and more than one request
requires write operations they can only be done one after
another. Also read during write is not allowed. The dba
extension uses locks to prevent this. See the following
table:
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