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Tie::Handle, Tie::StdHandle - base class definitions for tied handles
package NewHandle;
require Tie::Handle;
@ISA = qw(Tie::Handle);
sub READ { ... } # Provide a needed method
sub TIEHANDLE { ... } # Overrides inherited method
package main;
tie *FH, 'NewHandle';
This module provides some skeletal methods for handle-tying classes. See
the perltie manpage for a list of the functions required in tying a handle to a package.
The basic Tie::Handle package provides a new method, as well as methods
TIEHANDLE, PRINT, PRINTF and GETC.
For developers wishing to write their own tied-handle classes, the methods are summarized below. The the perltie manpage section not only documents these, but has sample code as well:
The method invoked by the command tie *glob, classname. Associates a new
glob instance with the specified class. LIST would represent additional
arguments (along the lines of the AnyDBM_File manpage and compatriots) needed to
complete the association.
Write length bytes of data from scalar starting at offset.
Print the values in LIST
Print the values in LIST using format
Read length bytes of data into scalar starting at offset.
Read a single line
Get a single character
Close the handle
(Re-)open the handle
Specify content is binary
Test for end of file.
Return position in the file.
Position the file.
Test for end of file.
Free the storage associated with the tied handle referenced by this. This is rarely needed, as Perl manages its memory quite well. But the option exists, should a class wish to perform specific actions upon the destruction of an instance.
The the perltie manpage section contains an example of tying handles.
This version of Tie::Handle is neither related to nor compatible with the Tie::Handle (3.0) module available on CPAN. It was due to an accident that two modules with the same name appeared. The namespace clash has been cleared in favor of this module that comes with the perl core in September 2000 and accordingly the version number has been bumped up to 4.0.