NAME

Tie::Handle - base class definitions for tied handles

SYNOPSIS

    package NewHandle;
    require Tie::Handle;
     
    @ISA = (Tie::Handle);
     
    sub READ { ... }            # Provide a needed method
    sub TIEHANDLE { ... }       # Overrides inherited method
         
     
    package main;
    
    tie *FH, 'NewHandle';

DESCRIPTION

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 TIESCALAR, FETCH and STORE. The new method is provided as a means of grandfathering, for classes that forget to provide their own TIESCALAR method.

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:

TIEHANDLE classname, LIST: 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 this, scalar, length, offset: Write length bytes of data from scalar starting at offset.
PRINT this, LIST: Print the values in LIST
PRINTF this, format, LIST: Print the values in LIST using format
READ this, scalar, length, offset: Read length bytes of data into scalar starting at offset.
READLINE this: Read a single line
GETC this: Get a single character
DESTROY this: 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.

MORE INFORMATION

The the perltie manpage section contains an example of tying handles.

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