tie::handle(3)

NAME

Tie::Handle, Tie::StdHandle - base class definitions for
tied handles

SYNOPSIS

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';

DESCRIPTION

This module provides some skeletal methods for handletying classes. See perltie 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 perltie
section not only documents these, but has sample code as
well:

TIEHANDLE classname, LIST: The method invoked by the command "tie *glob, class
name". Associates a new glob instance with the speci
fied class. "LIST" would represent additional argu
ments (along the lines of AnyDBM_File 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 off_ set.
READLINE this: Read a single line
GETC this: Get a single character
CLOSE this: Close the handle
OPEN this, filename: (Re-)open the handle
BINMODE this: Specify content is binary
EOF this: Test for end of file.
TELL this: Return position in the file.
SEEK this, offset, whence: Position the file.; Test for end of file.
DESTROY this: Free the storage associated with the tied handle ref
erenced by this. This is rarely needed, as Perl man
ages 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 perltie section contains an example of tying handles.

COMPATIBILITY

This version of Tie::Handle is neither related to nor com
patible 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.

docs.sk