NAME

Tk::Event - ToolKit for Events

SYNOPSIS

use Tk::Event; Tk::Event->fileevent(\*FH, readable => callback); Tk::Event->lineavail(\*FH, callback); use Tk::Event::Signal qw(INT); $SIG{INT} = callback; use Tk::Event::process; Tk::Event->proc($pid, callback); QueueEvent(callback [, position])

DESCRIPTION

That is better than nothing but still hard to use. Most scripts want higher level result (a line, a block of data etc.)

So it has occured to me that we could use new-ish TIEHANDLE thus:

my $obj = tie SOMEHANDLE,Tk::Event::IO; while (<SOMEHANDLE>) { }

Then the READLINE routine registers a callback and looks something like:

sub READLINE { my $obj = shift; Event->io(*$obj,readable,sub { sysread(*$obj,${*$obj},1,length(${*$obj}) }); my $pos; while (($pos = index(${*$obj},$/) < 0) { DoOneEvent(); } Event->io(*$obj,readable,); # unregister $pos += length($/); my $result = substr(${*$obj},0,$pos); substr(${*$obj},0,$pos) = ; return $result; }

This is using the scalar part of the glob representing the _inner_ IO as a buffer in which to accumulate chars.