NAME
BTRIEVE::FileIO - Btrieve file I/O operations
SYNOPSIS
use
BTRIEVE::FileIO();
my
$B
= BTRIEVE::FileIO->Open(
'TEST.BTR'
);
$B
->{Size} = 13;
for
(
$B
->StepFirst;
$B
->IsOk;
$B
->StepNext )
{
join
(
':'
,
unpack
(
'A3A10'
,
$B
->{Data} ) ),
"\n"
;
}
$B
->{Key} = 103;
for
(
$B
->GetEqual;
$B
->IsOk;
$B
->GetNext )
{
join
(
':'
,
unpack
(
'A3A10'
,
$B
->{Data} ) ),
"\n"
;
}
DESCRIPTION
This module provides methods for common Btrieve operations.
Methods
- Create( $FileName, $FileSpec, $KeySpecs )
-
Creates a Btrieve file. This is a constructor method and returns an BTRIEVE::FileIO object.
$FileSpec is a hash reference with the following defaults:
LogicalRecordLength
=> 128
PageSize
=> 512
FileFlags
=> 0
NumberOfDuplicatePointersToReserve
=> 0
Allocation
=> 0
$KeySpecs is an array reference of hash references with the following defaults:
KeyPosition
=> 1
KeyLength
=> 1
KeyFlags
=> 0
ExtendedDataType
=> 0
NullValue
=> 0
ManuallyAssignedKeyNumber
=> 0
- Open( $FileName )
-
Opens a Btrieve file. This is a constructor method and returns an BTRIEVE::FileIO object.
- Close
-
Closes a Btrieve file associated with an BTRIEVE::FileIO object. This method is called automatically from within DESTROY.
- IsOk
-
Tests the Status property. It returns true if Status indicates success and false if Status indicates an error.
- Insert( $Data )
-
Inserts $Data into the Btrieve file. If $Data is omitted, the Data property is used instead.
- StepFirst
-
Retrieves the physical first record of the file.
- StepLast
-
Retrieves the physical last record of the file.
- StepNext
-
Retrieves the physical next record of the file.
- StepPrevious
-
Retrieves the physical previous record of the file.
- GetFirst
-
Retrieves the logical first record of the file, based on the KeyNum property.
- GetLast
-
Retrieves the logical last record of the file, based on the KeyNum property.
- GetEqual
-
Retrieves a record which key is equal to the one specified by the Key/KeyNum properties.
- GetGreater
-
Retrieves a record which key is greater than the one specified by the Key/KeyNum properties.
- GetNext
-
Retrieves the logical next record of the file.
- GetPrevious
-
Retrieves the logical previous record of the file.
Properties
- Data
-
The data buffer used to transfer data from and to the Btrieve file.
- Size
-
The size of the data buffer. Default is 255.
- KeyNum
-
The number of the key used for logical (key based) data retrieval operations. Default is 0.
- Key
-
The buffer of the key used for logical (key based) data retrieval operations.
- Status
-
The status code. This is the return value of the native Btrieve call. It contains 0 for success or a native error code.
AUTHOR
Steffen Goeldner <sgoeldner@cpan.org>
COPYRIGHT
Copyright (c) 2004 Steffen Goeldner. All rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.