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+
+=head1 NAME
+
+Tk::Event - ToolKit for Events
+
+=for category Implementation
+
+=head1 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])
+
+
+=head1 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.
+
+=cut