poe::wheel::curses(3pm) [debian man page]

POE::Wheel::Curses(3pm) 				User Contributed Perl Documentation				   POE::Wheel::Curses(3pm)

NAME

       POE::Wheel::Curses - non-blocking input for Curses

SYNOPSIS

	 use Curses;
	 use POE qw(Wheel::Curses);

	 POE::Session->create(
	   inline_states => {
	     _start => sub {
	       $_[HEAP]{console} = POE::Wheel::Curses->new(
		 InputEvent => 'got_keystroke',
	       );
	     },
	     got_keystroke => sub {
	       my $keystroke = $_[ARG0];

	       # Make control and extended keystrokes printable.
	       if ($keystroke lt ' ') {
		 $keystroke = '<' . uc(unctrl($keystroke)) . '>';
	       }
	       elsif ($keystroke =~ /^d{2,}$/) {
		 $keystroke = '<' . uc(keyname($keystroke)) . '>';
	       }

	       # Just display it.
	       addstr($keystroke);
	       noutrefresh();
	       doupdate;

	       # Gotta exit somehow.
	       delete $_[HEAP]{console} if $keystroke eq "<^C>";
	     },
	   }
	 );

	 POE::Kernel->run();
	 exit;

DESCRIPTION

       POE::Wheel::Curses implements non-blocking input for Curses programs.

       POE::Wheel::Curses will emit an "InputEvent" of your choosing whenever an input event is registered on a recognized input device (keyboard
       and sometimes mouse, depending on the curses library).  Meanwhile, applications can be doing other things like monitoring network
       connections or child processes, or managing timers and stuff.

PUBLIC METHODS

       POE::Wheel::Curses is rather simple.

   new
       new() creates a new POE::Wheel::Curses object.  During construction, the wheel registers an input watcher for STDIN (via select_read()) and
       registers an internal handler to preprocess keystrokes.

       new() accepts only one parameter "InputEvent".  "InputEvent" contains the name of the event that the wheel will emit whenever there is
       input on the console or terminal.  As with all wheels, the event will be sent to the session that was active when the wheel was
       constructed.

       It should be noted that an application may only have one active POE::Wheel::Curses object.

EVENTS AND PARAMETERS

       These are the events sent by POE::Wheel::Curses.

   InputEvent
       "InputEvent" defines the event that will be emitted when POE::Wheel::Curses detects and reads console input.  This event includes two
       parameters:

       $_[ARG0] contains the raw keystroke as received by Curses::getch().  An application may process the keystroke using Curses::unctrl() and
       Curses::keyname() on the keystroke.

       $_[ARG1] contains the POE::Wheel::Curses object's ID.

       Mouse events aren't portable.  As of October 2009, it's up to the application to decide whether to call mousemask().

SEE ALSO

       Curses documents what can be done with Curses.  Also see the man page for whichever version of libcurses happens to be installed (curses,
       ncurses, etc.).

       POE::Wheel describes wheels in general.

       The SEE ALSO section in POE contains a table of contents covering the entire POE distribution.

BUGS

       None known, although curses implementations vary widely.

AUTHORS &; COPYRIGHTS
       Please see POE for more information about authors and contributors.

perl v5.14.2							    2012-05-15						   POE::Wheel::Curses(3pm)

POE::Filter::Line(3pm)					User Contributed Perl Documentation				    POE::Filter::Line(3pm)

NAME

       POE::Filter::Line - serialize and parse terminated records (lines)

SYNOPSIS

	 #!perl

	 use POE qw(Wheel::FollowTail Filter::Line);

	 POE::Session->create(
	   inline_states => {
	     _start => sub {
	       $_[HEAP]{tailor} = POE::Wheel::FollowTail->new(
		 Filename => "/var/log/system.log",
		 InputEvent => "got_log_line",
		 Filter => POE::Filter::Line->new(),
	       );
	     },
	     got_log_line => sub {
	       print "Log: $_[ARG0]
";
	     }
	   }
	 );

	 POE::Kernel->run();
	 exit;

DESCRIPTION

       POE::Filter::Line parses stream data into terminated records.  The default parser interprets newlines as the record terminator, and the
       default serializer appends network newlines (CR/LF, or "x0Dx0A") to outbound records.

       Record terminators are removed from the data POE::Filter::Line returns.

       POE::Filter::Line supports a number of other ways to parse lines.  Constructor parameters may specify literal newlines, regular
       expressions, or that the filter should detect newlines on its own.

PUBLIC FILTER METHODS

       POE::Filter::Line's new() method has some interesting parameters.

   new
       new() accepts a list of named parameters.

       In all cases, the data interpreted as the record terminator is stripped from the data POE::Filter::Line returns.

       "InputLiteral" may be used to parse records that are terminated by some literal string.	For example, POE::Filter::Line may be used to
       parse and emit C-style lines, which are terminated with an ASCII NUL:

	 my $c_line_filter = POE::Filter::Line->new(
	   InputLiteral => chr(0),
	   OutputLiteral => chr(0),
	 );

       "OutputLiteral" allows a filter to put() records with a different record terminator than it parses.  This can be useful in applications
       that must translate record terminators.

       "Literal" is a shorthand for the common case where the input and output literals are identical.	The previous example may be written as:

	 my $c_line_filter = POE::Filter::Line->new(
	   Literal => chr(0),
	 );

       An application can also allow POE::Filter::Line to figure out which newline to use.  This is done by specifying "InputLiteral" to be undef:

	 my $whichever_line_filter = POE::Filter::Line->new(
	   InputLiteral => undef,
	   OutputLiteral => "
",
	 );

       "InputRegexp" may be used in place of "InputLiteral" to recognize line terminators based on a regular expression.  In this example, input
       is terminated by two or more consecutive newlines.  On output, the paragraph separator is "---" on a line by itself.

	 my $paragraph_filter = POE::Filter::Line->new(
	   InputRegexp => "([x0Dx0A]{2,})",
	   OutputLiteral => "
---
",
	 );

PUBLIC FILTER METHODS

       POE::Filter::Line has no additional public methods.

SEE ALSO

       Please see POE::Filter for documentation regarding the base interface.

       The SEE ALSO section in POE contains a table of contents covering the entire POE distribution.

BUGS

       The default input newline parser is a regexp that has an unfortunate race condition.  First the regular expression:

	 /(x0Dx0A?|x0Ax0D?)/

       While it quickly recognizes most forms of newline, it can sometimes detect an extra blank line.	This happens when a two-byte newline
       character is broken between two reads.  Consider this situation:

	 some stream dataCR
	 LFother stream data

       The regular expression will see the first CR without its corresponding LF.  The filter will properly return "some stream data" as a line.
       When the next packet arrives, the leading "LF" will be treated as the terminator for a 0-byte line.  The filter will faithfully return this
       empty line.

       It is advised to specify literal newlines or use the autodetect feature in applications where blank lines are significant.

AUTHORS &; COPYRIGHTS
       Please see POE for more information about authors and contributors.

perl v5.14.2							    2012-05-15						    POE::Filter::Line(3pm)