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.