NAME
    rxvtperl - rxvt-unicode's embedded perl interpreter

SYNOPSIS
       # create a file grab_test in $HOME:

       sub on_sel_grab {
          warn "you selected ", $_[0]->selection;
          ()
       }

       # start a rxvt using it:

       rxvt --perl-lib $HOME -pe grab_test

DESCRIPTION
    Every time a terminal object gets created, extension scripts specified
    via the "perl" resource are loaded and associated with it.

    Scripts are compiled in a 'use strict' and 'use utf8' environment, and
    thus must be encoded as UTF-8.

    Each script will only ever be loaded once, even in rxvtd, where scripts
    will be shared (but not enabled) for all terminals.

PREPACKAGED EXTENSIONS
    This section describes the extensions delivered with this release. You
    can find them in /opt/rxvt/lib/urxvt/perl/.

    You can activate them like this:

      rxvt -pe <extensionname>

    Or by adding them to the resource for extensions loaded by default:

      URxvt.perl-ext-common: default,automove-background,selection-autotransform

    selection (enabled by default)
        (More) intelligent selection. This extension tries to be more
        intelligent when the user extends selections (double-click and
        further clicks). Right now, it tries to select words, urls and
        complete shell-quoted arguments, which is very convenient, too, if
        your ls supports "--quoting-style=shell".

        A double-click usually selects the word under the cursor, further
        clicks will enlarge the selection.

        The selection works by trying to match a number of regexes and
        displaying them in increasing order of length. You can add your own
        regexes by specifying resources of the form:

           URxvt.selection.pattern-0: perl-regex
           URxvt.selection.pattern-1: perl-regex
           ...

        The index number (0, 1...) must not have any holes, and each regex
        must contain at least one pair of capturing parentheses, which will
        be used for the match. For example, the following adds a regex that
        matches everything between two vertical bars:

           URxvt.selection.pattern-0: \\|([^|]+)\\|

        Another example: Programs I use often output "absolute path: " at
        the beginning of a line when they process multiple files. The
        following pattern matches the filename (note, there is a single
        space at the very end):

           URxvt.selection.pattern-0: ^(/[^:]+):\ 

        You can look at the source of the selection extension to see more
        interesting uses, such as parsing a line from beginning to end.

        This extension also offers following bindable keyboard commands:

        rot13
            Rot-13 the selection when activated. Used via keyboard trigger:

               URxvt.keysym.C-M-r: perl:selection:rot13

    option-popup (enabled by default)
        Binds a popup menu to Ctrl-Button2 that lets you toggle (some)
        options at runtime.

        Other extensions can extend this popup menu by pushing a code
        reference onto "@{ $term-"{option_popup_hook} }>, which gets called
        whenever the popup is being displayed.

        It's sole argument is the popup menu, which can be modified. It
        should either return nothing or a string, the initial boolean value
        and a code reference. The string will be used as button text and the
        code reference will be called when the toggle changes, with the new
        boolean value as first argument.

        The following will add an entry "myoption" that changes
        "$self-"{myoption}>:

           push @{ $self->{term}{option_popup_hook} }, sub {
              ("my option" => $myoption, sub { $self->{myoption} = $_[0] })
           };

    selection-popup (enabled by default)
        Binds a popup menu to Ctrl-Button3 that lets you convert the
        selection text into various other formats/action (such as uri
        unescaping, perl evaluation, web-browser starting etc.), depending
        on content.

        Other extensions can extend this popup menu by pushing a code
        reference onto "@{ $term-"{selection_popup_hook} }>, which gets
        called whenever the popup is being displayed.

        It's sole argument is the popup menu, which can be modified. The
        selection is in $_, which can be used to decide whether to add
        something or not. It should either return nothing or a string and a
        code reference. The string will be used as button text and the code
        reference will be called when the button gets activated and should
        transform $_.

        The following will add an entry "a to b" that transforms all "a"s in
        the selection to "b"s, but only if the selection currently contains
        any "a"s:

           push @{ $self->{term}{selection_popup_hook} }, sub {
              /a/ ? ("a to be" => sub { s/a/b/g }
                  : ()
           };

    searchable-scrollback<hotkey> (enabled by default)
        Adds regex search functionality to the scrollback buffer, triggered
        by a hotkey (default: "M-s"). While in search mode, normal terminal
        input/output is suspended and a regex is displayed at the bottom of
        the screen.

        Inputting characters appends them to the regex and continues
        incremental search. "BackSpace" removes a character from the regex,
        "Up" and "Down" search upwards/downwards in the scrollback buffer,
        "End" jumps to the bottom. "Escape" leaves search mode and returns
        to the point where search was started, while "Enter" or "Return"
        stay at the current position and additionally stores the first match
        in the current line into the primary selection.

        The regex defaults to "(?i)", resulting in a case-insensitive
        search. To get a case-sensitive search you can delete this prefix
        using "BackSpace" or simply use an uppercase character which removes
        the "(?i)" prefix.

        See perlre for more info about perl regular expression syntax.

    readline (enabled by default)
        A support package that tries to make editing with readline easier.
        At the moment, it reacts to clicking shift-left mouse button by
        trying to move the text cursor to this position. It does so by
        generating as many cursor-left or cursor-right keypresses as
        required (the this only works for programs that correctly support
        wide characters).

        To avoid too many false positives, this is only done when:

        - the tty is in ICANON state.
        - the text cursor is visible.
        - the primary screen is currently being displayed.
        - the mouse is on the same (multi-row-) line as the text cursor.

        The normal selection mechanism isn't disabled, so quick successive
        clicks might interfere with selection creation in harmless ways.

    selection-autotransform
        This selection allows you to do automatic transforms on a selection
        whenever a selection is made.

        It works by specifying perl snippets (most useful is a single "s///"
        operator) that modify $_ as resources:

           URxvt.selection-autotransform.0: transform
           URxvt.selection-autotransform.1: transform
           ...

        For example, the following will transform selections of the form
        "filename:number", often seen in compiler messages, into "vi
        +$filename $word":

           URxvt.selection-autotransform.0: s/^([^:[:space:]]+):(\\d+):?$/vi +$2 \\Q$1\\E\\x0d/

        And this example matches the same,but replaces it with vi-commands
        you can paste directly into your (vi :) editor:

           URxvt.selection-autotransform.0: s/^([^:[:space:]]+(\\d+):?$/:e \\Q$1\\E\\x0d:$2\\x0d/

        Of course, this can be modified to suit your needs and your editor
        :)

        To expand the example above to typical perl error messages ("XXX at
        FILENAME line YYY."), you need a slightly more elaborate solution:

           URxvt.selection.pattern-0: ( at .*? line \\d+[,.])
           URxvt.selection-autotransform.0: s/^ at (.*?) line (\\d+)[,.]$/:e \\Q$1\E\\x0d:$2\\x0d/

        The first line tells the selection code to treat the unchanging part
        of every error message as a selection pattern, and the second line
        transforms the message into vi commands to load the file.

    tabbed
        This transforms the terminal into a tabbar with additional
        terminals, that is, it implements what is commonly referred to as
        "tabbed terminal". The topmost line displays a "[NEW]" button,
        which, when clicked, will add a new tab, followed by one button per
        tab.

        Clicking a button will activate that tab. Pressing Shift-Left and
        Shift-Right will switch to the tab left or right of the current one,
        while Shift-Down creates a new tab.

        The tabbar itself can be configured similarly to a normal terminal,
        but with a resource class of "URxvt.tabbed". In addition, it
        supports the following four resources (shown with defaults):

           URxvt.tabbed.tabbar-fg: <colour-index, default 3>
           URxvt.tabbed.tabbar-bg: <colour-index, default 0>
           URxvt.tabbed.tab-fg:    <colour-index, default 0>
           URxvt.tabbed.tab-bg:    <colour-index, default 1>

        See *COLOR AND GRAPHICS* in the rxvt(1) manpage for valid indices.

    matcher
        Uses per-line display filtering ("on_line_update") to underline text
        matching a certain pattern and make it clickable. When clicked with
        the mouse button specified in the "matcher.button" resource (default
        2, or middle), the program specified in the "matcher.launcher"
        resource (default, the "urlLauncher" resource, "sensible-browser")
        will be started with the matched text as first argument. The default
        configuration is suitable for matching URLs and launching a web
        browser, like the former "mark-urls" extension.

        The default pattern to match URLs can be overridden with the
        "matcher.pattern.0" resource, and additional patterns can be
        specified with numbered patterns, in a manner similar to the
        "selection" extension. The launcher can also be overridden on a
        per-pattern basis.

        Example configuration:

            URxvt.perl-ext:           default,matcher
            URxvt.urlLauncher:        sensible-browser
            URxvt.keysym.C-Delete:    perl:matcher
            URxvt.matcher.button:     1
            URxvt.matcher.pattern.1:  \\bwww\\.[\\w-]+\\.[\\w./?&@#-]*[\\w/-]
            URxvt.matcher.pattern.2:  \\B(/\\S+?):(\\d+)(?=:|$)
            URxvt.matcher.launcher.2: gvim +$2 $1

    xim-onthespot
        This (experimental) perl extension implements OnTheSpot editing. It
        does not work perfectly, and some input methods don't seem to work
        well with OnTheSpot editing in general, but it seems to work at
        leats for SCIM and kinput2.

        You enable it by specifying this extension and a preedit style of
        "OnTheSpot", i.e.:

           rxvt -pt OnTheSpot -pe xim-onthespot

    kuake<hotkey>
        A very primitive quake-console-like extension. It was inspired by a
        description of how the programs "kuake" and "yakuake" work: Whenever
        the user presses a global accelerator key (by default "F10"), the
        terminal will show or hide itself. Another press of the accelerator
        key will hide or show it again.

        Initially, the window will not be shown when using this extension.

        This is useful if you need a single terminal thats not using any
        desktop space most of the time but is quickly available at the press
        of a key.

        The accelerator key is grabbed regardless of any modifiers, so this
        extension will actually grab a physical key just for this function.

        If you want a quake-like animation, tell your window manager to do
        so (fvwm can do it).

    automove-background
        This is basically a very small extension that dynamically changes
        the background pixmap offset to the window position, in effect
        creating the same effect as pseudo transparency with a custom
        pixmap. No scaling is supported in this mode. Example:

           rxvt -pixmap background.xpm -pe automove-background

    block-graphics-to-ascii
        A not very useful example of filtering all text output to the
        terminal by replacing all line-drawing characters (U+2500 .. U+259F)
        by a similar-looking ascii character.

    digital-clock
        Displays a digital clock using the built-in overlay.

    remote-clipboard
        Somewhat of a misnomer, this extension adds two menu entries to the
        selection popup that allows one ti run external commands to store
        the selection somewhere and fetch it again.

        We use it to implement a "distributed selection mechanism", which
        just means that one command uploads the file to a remote server, and
        another reads it.

        The commands can be set using the "URxvt.remote-selection.store" and
        "URxvt.remote-selection.fetch" resources. The first should read the
        selection to store from STDIN (always in UTF-8), the second should
        provide the selection data on STDOUT (also in UTF-8).

        The defaults (which are likely useless to you) use rsh and cat:

           URxvt.remote-selection.store: rsh ruth 'cat >/tmp/distributed-selection'
           URxvt.remote-selection.fetch: rsh ruth 'cat /tmp/distributed-selection'

    selection-pastebin
        This is a little rarely useful extension that Uploads the selection
        as textfile to a remote site (or does other things). (The
        implementation is not currently secure for use in a multiuser
        environment as it writes to /tmp directly.).

        It listens to the "selection-pastebin:remote-pastebin" keyboard
        command, i.e.

           URxvt.keysym.C-M-e: perl:selection-pastebin:remote-pastebin

        Pressing this combination runs a command with "%" replaced by the
        name of the textfile. This command can be set via a resource:

           URxvt.selection-pastebin.cmd: rsync -apP % ruth:/var/www/www.ta-sa.org/files/txt/.

        And the default is likely not useful to anybody but the few people
        around here :)

        The name of the textfile is the hex encoded md5 sum of the
        selection, so the same content should lead to the same filename.

        After a successful upload the selection will be replaced by the text
        given in the "selection-pastebin-url" resource (again, the % is the
        placeholder for the filename):

           URxvt.selection-pastebin.url: http://www.ta-sa.org/files/txt/%

        *Note to xrdb users:* xrdb uses the C preprocessor, which might
        interpret the double "/" characters as comment start. Use "\057\057"
        instead, which works regardless of wether xrdb is used to parse the
        resource file or not.

    example-refresh-hooks
        Displays a very simple digital clock in the upper right corner of
        the window. Illustrates overwriting the refresh callbacks to create
        your own overlays or changes.

API DOCUMENTATION
  General API Considerations
    All objects (such as terminals, time watchers etc.) are typical
    reference-to-hash objects. The hash can be used to store anything you
    like. All members starting with an underscore (such as "_ptr" or
    "_hook") are reserved for internal uses and MUST NOT be accessed or
    modified).

    When objects are destroyed on the C++ side, the perl object hashes are
    emptied, so its best to store related objects such as time watchers and
    the like inside the terminal object so they get destroyed as soon as the
    terminal is destroyed.

    Argument names also often indicate the type of a parameter. Here are
    some hints on what they mean:

    $text
        Rxvt-unicodes special way of encoding text, where one "unicode"
        character always represents one screen cell. See ROW_t for a
        discussion of this format.

    $string
        A perl text string, with an emphasis on *text*. It can store all
        unicode characters and is to be distinguished with text encoded in a
        specific encoding (often locale-specific) and binary data.

    $octets
        Either binary data or - more common - a text string encoded in a
        locale-specific way.

  Extension Objects
    Every perl extension is a perl class. A separate perl object is created
    for each terminal, and each terminal has its own set of extenion
    objects, which are passed as the first parameter to hooks. So extensions
    can use their $self object without having to think about clashes with
    other extensions or other terminals, with the exception of methods and
    members that begin with an underscore character "_": these are reserved
    for internal use.

    Although it isn't a "urxvt::term" object, you can call all methods of
    the "urxvt::term" class on this object.

    It has the following methods and data members:

    $urxvt_term = $self->{term}
        Returns the "urxvt::term" object associated with this instance of
        the extension. This member *must not* be changed in any way.

    $self->enable ($hook_name => $cb, [$hook_name => $cb..])
        Dynamically enable the given hooks (named without the "on_" prefix)
        for this extension, replacing any previous hook. This is useful when
        you want to overwrite time-critical hooks only temporarily.

    $self->disable ($hook_name[, $hook_name..])
        Dynamically disable the given hooks.

  Hooks
    The following subroutines can be declared in extension files, and will
    be called whenever the relevant event happens.

    The first argument passed to them is an extension object as described in
    the in the "Extension Objects" section.

    All of these hooks must return a boolean value. If any of the called
    hooks returns true, then the event counts as being *consumed*, and the
    relevant action might not be carried out by the C++ code.

    *When in doubt, return a false value (preferably "()").*

    on_init $term
        Called after a new terminal object has been initialized, but before
        windows are created or the command gets run. Most methods are unsafe
        to call or deliver senseless data, as terminal size and other
        characteristics have not yet been determined. You can safely query
        and change resources and options, though. For many purposes the
        "on_start" hook is a better place.

    on_start $term
        Called at the very end of initialisation of a new terminal, just
        before trying to map (display) the toplevel and returning to the
        main loop.

    on_destroy $term
        Called whenever something tries to destroy terminal, when the
        terminal is still fully functional (not for long, though).

    on_reset $term
        Called after the screen is "reset" for any reason, such as resizing
        or control sequences. Here is where you can react on changes to
        size-related variables.

    on_child_start $term, $pid
        Called just after the child process has been "fork"ed.

    on_child_exit $term, $status
        Called just after the child process has exited. $status is the
        status from "waitpid".

    on_sel_make $term, $eventtime
        Called whenever a selection has been made by the user, but before
        the selection text is copied, so changes to the beginning, end or
        type of the selection will be honored.

        Returning a true value aborts selection making by urxvt, in which
        case you have to make a selection yourself by calling
        "$term->selection_grab".

    on_sel_grab $term, $eventtime
        Called whenever a selection has been copied, but before the
        selection is requested from the server. The selection text can be
        queried and changed by calling "$term->selection".

        Returning a true value aborts selection grabbing. It will still be
        highlighted.

    on_sel_extend $term
        Called whenever the user tries to extend the selection (e.g. with a
        double click) and is either supposed to return false (normal
        operation), or should extend the selection itself and return true to
        suppress the built-in processing. This can happen multiple times, as
        long as the callback returns true, it will be called on every
        further click by the user and is supposed to enlarge the selection
        more and more, if possible.

        See the selection example extension.

    on_view_change $term, $offset
        Called whenever the view offset changes, i.e. the user or program
        scrolls. Offset 0 means display the normal terminal, positive values
        show this many lines of scrollback.

    on_scroll_back $term, $lines, $saved
        Called whenever lines scroll out of the terminal area into the
        scrollback buffer. $lines is the number of lines scrolled out and
        may be larger than the scroll back buffer or the terminal.

        It is called before lines are scrolled out (so rows 0 .. min ($lines
        - 1, $nrow - 1) represent the lines to be scrolled out). $saved is
        the total number of lines that will be in the scrollback buffer.

    on_osc_seq $term, $op, $args
        Called on every OSC sequence and can be used to suppress it or
        modify its behaviour. The default should be to return an empty list.
        A true value suppresses execution of the request completely. Make
        sure you don't get confused by recursive invocations when you output
        an osc sequence within this callback.

        "on_osc_seq_perl" should be used for new behaviour.

    on_osc_seq_perl $term, $string
        Called whenever the ESC ] 777 ; string ST command sequence (OSC =
        operating system command) is processed. Cursor position and other
        state information is up-to-date when this happens. For
        interoperability, the string should start with the extension name
        and a colon, to distinguish it from commands for other extensions,
        and this might be enforced in the future.

        Be careful not ever to trust (in a security sense) the data you
        receive, as its source can not easily be controlled (e-mail content,
        messages from other users on the same system etc.).

    on_add_lines $term, $string
        Called whenever text is about to be output, with the text as
        argument. You can filter/change and output the text yourself by
        returning a true value and calling "$term->scr_add_lines" yourself.
        Please note that this might be very slow, however, as your hook is
        called for all text being output.

    on_tt_write $term, $octets
        Called whenever some data is written to the tty/pty and can be used
        to suppress or filter tty input.

    on_line_update $term, $row
        Called whenever a line was updated or changed. Can be used to filter
        screen output (e.g. underline urls or other useless stuff). Only
        lines that are being shown will be filtered, and, due to performance
        reasons, not always immediately.

        The row number is always the topmost row of the line if the line
        spans multiple rows.

        Please note that, if you change the line, then the hook might get
        called later with the already-modified line (e.g. if unrelated parts
        change), so you cannot just toggle rendition bits, but only set
        them.

    on_refresh_begin $term
        Called just before the screen gets redrawn. Can be used for overlay
        or similar effects by modify terminal contents in refresh_begin, and
        restoring them in refresh_end. The built-in overlay and selection
        display code is run after this hook, and takes precedence.

    on_refresh_end $term
        Called just after the screen gets redrawn. See "on_refresh_begin".

    on_user_command $term, $string
        Called whenever a user-configured event is being activated (e.g. via
        a "perl:string" action bound to a key, see description of the keysym
        resource in the rxvt(1) manpage).

        The event is simply the action string. This interface is assumed to
        change slightly in the future.

    on_resize_all_windows $tern, $new_width, $new_height
        Called just after the new window size has been calculated, but
        before windows are actually being resized or hints are being set. If
        this hook returns TRUE, setting of the window hints is being
        skipped.

    on_x_event $term, $event
        Called on every X event received on the vt window (and possibly
        other windows). Should only be used as a last resort. Most event
        structure members are not passed.

    on_root_event $term, $event
        Like "on_x_event", but is called for events on the root window.

    on_focus_in $term
        Called whenever the window gets the keyboard focus, before
        rxvt-unicode does focus in processing.

    on_focus_out $term
        Called whenever the window loses keyboard focus, before rxvt-unicode
        does focus out processing.

    on_configure_notify $term, $event
    on_property_notify $term, $event
    on_key_press $term, $event, $keysym, $octets
    on_key_release $term, $event, $keysym
    on_button_press $term, $event
    on_button_release $term, $event
    on_motion_notify $term, $event
    on_map_notify $term, $event
    on_unmap_notify $term, $event
        Called whenever the corresponding X event is received for the
        terminal If the hook returns true, then the even will be ignored by
        rxvt-unicode.

        The event is a hash with most values as named by Xlib (see the
        XEvent manpage), with the additional members "row" and "col", which
        are the (real, not screen-based) row and column under the mouse
        cursor.

        "on_key_press" additionally receives the string rxvt-unicode would
        output, if any, in locale-specific encoding.

        subwindow.

    on_client_message $term, $event
    on_wm_protocols $term, $event
    on_wm_delete_window $term, $event
        Called when various types of ClientMessage events are received (all
        with format=32, WM_PROTOCOLS or WM_PROTOCOLS:WM_DELETE_WINDOW).

  Variables in the "urxvt" Package
    $urxvt::LIBDIR
        The rxvt-unicode library directory, where, among other things, the
        perl modules and scripts are stored.

    $urxvt::RESCLASS, $urxvt::RESCLASS
        The resource class and name rxvt-unicode uses to look up X
        resources.

    $urxvt::RXVTNAME
        The basename of the installed binaries, usually "urxvt".

    $urxvt::TERM
        The current terminal. This variable stores the current "urxvt::term"
        object, whenever a callback/hook is executing.

    @urxvt::TERM_INIT
        All code references in this array will be called as methods of the
        next newly created "urxvt::term" object (during the "on_init"
        phase). The array gets cleared before the code references that were
        in it are being executed, so references can push themselves onto it
        again if they so desire.

        This complements to the perl-eval command line option, but gets
        executed first.

    @urxvt::TERM_EXT
        Works similar to @TERM_INIT, but contains perl package/class names,
        which get registered as normal extensions after calling the hooks in
        @TERM_INIT but before other extensions. Gets cleared just like
        @TERM_INIT.

  Functions in the "urxvt" Package
    urxvt::fatal $errormessage
        Fatally aborts execution with the given error message. Avoid at all
        costs! The only time this is acceptable is when the terminal process
        starts up.

    urxvt::warn $string
        Calls "rxvt_warn" with the given string which should not include a
        newline. The module also overwrites the "warn" builtin with a
        function that calls this function.

        Using this function has the advantage that its output ends up in the
        correct place, e.g. on stderr of the connecting urxvtc client.

        Messages have a size limit of 1023 bytes currently.

    @terms = urxvt::termlist
        Returns all urxvt::term objects that exist in this process,
        regardless of whether they are started, being destroyed etc., so be
        careful. Only term objects that have perl extensions attached will
        be returned (because there is no urxvt::term objet associated with
        others).

    $time = urxvt::NOW
        Returns the "current time" (as per the event loop).

    urxvt::CurrentTime
    urxvt::ShiftMask, LockMask, ControlMask, Mod1Mask, Mod2Mask, Mod3Mask,
    Mod4Mask, Mod5Mask, Button1Mask, Button2Mask, Button3Mask, Button4Mask,
    Button5Mask, AnyModifier
    urxvt::NoEventMask, KeyPressMask, KeyReleaseMask, ButtonPressMask,
    ButtonReleaseMask, EnterWindowMask, LeaveWindowMask, PointerMotionMask,
    PointerMotionHintMask, Button1MotionMask, Button2MotionMask,
    Button3MotionMask, Button4MotionMask, Button5MotionMask,
    ButtonMotionMask, KeymapStateMask, ExposureMask, VisibilityChangeMask,
    StructureNotifyMask, ResizeRedirectMask, SubstructureNotifyMask,
    SubstructureRedirectMask, FocusChangeMask, PropertyChangeMask,
    ColormapChangeMask, OwnerGrabButtonMask
    urxvt::KeyPress, KeyRelease, ButtonPress, ButtonRelease, MotionNotify,
    EnterNotify, LeaveNotify, FocusIn, FocusOut, KeymapNotify, Expose,
    GraphicsExpose, NoExpose, VisibilityNotify, CreateNotify, DestroyNotify,
    UnmapNotify, MapNotify, MapRequest, ReparentNotify, ConfigureNotify,
    ConfigureRequest, GravityNotify, ResizeRequest, CirculateNotify,
    CirculateRequest, PropertyNotify, SelectionClear, SelectionRequest,
    SelectionNotify, ColormapNotify, ClientMessage, MappingNotify
        Various constants for use in X calls and event processing.

  RENDITION
    Rendition bitsets contain information about colour, font, font styles
    and similar information for each screen cell.

    The following "macros" deal with changes in rendition sets. You should
    never just create a bitset, you should always modify an existing one, as
    they contain important information required for correct operation of
    rxvt-unicode.

    $rend = urxvt::DEFAULT_RSTYLE
        Returns the default rendition, as used when the terminal is starting
        up or being reset. Useful as a base to start when creating
        renditions.

    $rend = urxvt::OVERLAY_RSTYLE
        Return the rendition mask used for overlays by default.

    $rendbit = urxvt::RS_Bold, RS_Italic, RS_Blink, RS_RVid, RS_Uline
        Return the bit that enabled bold, italic, blink, reverse-video and
        underline, respectively. To enable such a style, just logically OR
        it into the bitset.

    $foreground = urxvt::GET_BASEFG $rend
    $background = urxvt::GET_BASEBG $rend
        Return the foreground/background colour index, respectively.

    $rend = urxvt::SET_FGCOLOR $rend, $new_colour
    $rend = urxvt::SET_BGCOLOR $rend, $new_colour
    $rend = urxvt::SET_COLOR $rend, $new_fg, $new_bg
        Replace the foreground/background colour in the rendition mask with
        the specified one.

    $value = urxvt::GET_CUSTOM $rend
        Return the "custom" value: Every rendition has 5 bits for use by
        extensions. They can be set and changed as you like and are
        initially zero.

    $rend = urxvt::SET_CUSTOM $rend, $new_value
        Change the custom value.

  The "urxvt::anyevent" Class
    The sole purpose of this class is to deliver an interface to the
    "AnyEvent" module - any module using it will work inside urxvt without
    further programming. The only exception is that you cannot wait on
    condition variables, but non-blocking condvar use is ok. What this means
    is that you cannot use blocking APIs, but the non-blocking variant
    should work.

  The "urxvt::term" Class
    $term = new urxvt::term $envhashref, $rxvtname, [arg...]
        Creates a new terminal, very similar as if you had started it with
        system "$rxvtname, arg...". $envhashref must be a reference to a
        %ENV-like hash which defines the environment of the new terminal.

        Croaks (and probably outputs an error message) if the new instance
        couldn't be created. Returns "undef" if the new instance didn't
        initialise perl, and the terminal object otherwise. The "init" and
        "start" hooks will be called before this call returns, and are free
        to refer to global data (which is race free).

    $term->destroy
        Destroy the terminal object (close the window, free resources etc.).
        Please note that rxvt will not exit as long as any event watchers
        (timers, io watchers) are still active.

    $term->exec_async ($cmd[, @args])
        Works like the combination of the "fork"/"exec" builtins, which
        executes ("starts") programs in the background. This function takes
        care of setting the user environment before exec'ing the command
        (e.g. "PATH") and should be preferred over explicit calls to "exec"
        or "system".

        Returns the pid of the subprocess or "undef" on error.

    $isset = $term->option ($optval[, $set])
        Returns true if the option specified by $optval is enabled, and
        optionally change it. All option values are stored by name in the
        hash %urxvt::OPTION. Options not enabled in this binary are not in
        the hash.

        Here is a likely non-exhaustive list of option names, please see the
        source file /src/optinc.h to see the actual list:

         borderLess console cursorBlink cursorUnderline hold iconic insecure
         intensityStyles jumpScroll loginShell mapAlert meta8 mouseWheelScrollPage
         override-redirect pastableTabs pointerBlank reverseVideo scrollBar
         scrollBar_floating scrollBar_right scrollTtyKeypress scrollTtyOutput
         scrollWithBuffer secondaryScreen secondaryScroll skipBuiltinGlyphs
         transparent tripleclickwords utmpInhibit visualBell

    $value = $term->resource ($name[, $newval])
        Returns the current resource value associated with a given name and
        optionally sets a new value. Setting values is most useful in the
        "init" hook. Unset resources are returned and accepted as "undef".

        The new value must be properly encoded to a suitable character
        encoding before passing it to this method. Similarly, the returned
        value may need to be converted from the used encoding to text.

        Resource names are as defined in src/rsinc.h. Colours can be
        specified as resource names of the form "color+<index>", e.g.
        "color+5". (will likely change).

        Please note that resource strings will currently only be freed when
        the terminal is destroyed, so changing options frequently will eat
        memory.

        Here is a likely non-exhaustive list of resource names, not all of
        which are supported in every build, please see the source file
        /src/rsinc.h to see the actual list:

          answerbackstring backgroundPixmap backspace_key boldFont boldItalicFont
          borderLess color cursorBlink cursorUnderline cutchars delete_key
          display_name embed ext_bwidth fade font geometry hold iconName
          imFont imLocale inputMethod insecure int_bwidth intensityStyles
          italicFont jumpScroll lineSpace loginShell mapAlert meta8 modifier
          mouseWheelScrollPage name override_redirect pastableTabs path perl_eval
          perl_ext_1 perl_ext_2 perl_lib pointerBlank pointerBlankDelay
          preeditType print_pipe pty_fd reverseVideo saveLines scrollBar
          scrollBar_align scrollBar_floating scrollBar_right scrollBar_thickness
          scrollTtyKeypress scrollTtyOutput scrollWithBuffer scrollstyle
          secondaryScreen secondaryScroll selectstyle shade term_name title
          transient_for transparent transparent_all tripleclickwords utmpInhibit
          visualBell

    $value = $term->x_resource ($pattern)
        Returns the X-Resource for the given pattern, excluding the program
        or class name, i.e. "$term->x_resource ("boldFont")" should return
        the same value as used by this instance of rxvt-unicode. Returns
        "undef" if no resource with that pattern exists.

        This method should only be called during the "on_start" hook, as
        there is only one resource database per display, and later
        invocations might return the wrong resources.

    $success = $term->parse_keysym ($keysym_spec, $command_string)
        Adds a keymap translation exactly as specified via a resource. See
        the "keysym" resource in the rxvt(1) manpage.

    $rend = $term->rstyle ([$new_rstyle])
        Return and optionally change the current rendition. Text that is
        output by the terminal application will use this style.

    ($row, $col) = $term->screen_cur ([$row, $col])
        Return the current coordinates of the text cursor position and
        optionally set it (which is usually bad as applications don't expect
        that).

    ($row, $col) = $term->selection_mark ([$row, $col])
    ($row, $col) = $term->selection_beg ([$row, $col])
    ($row, $col) = $term->selection_end ([$row, $col])
        Return the current values of the selection mark, begin or end
        positions, and optionally set them to new values.

    $term->selection_make ($eventtime[, $rectangular])
        Tries to make a selection as set by "selection_beg" and
        "selection_end". If $rectangular is true (default: false), a
        rectangular selection will be made. This is the prefered function to
        make a selection.

    $success = $term->selection_grab ($eventtime)
        Try to request the primary selection text from the server (for
        example, as set by the next method). No visual feedback will be
        given. This function is mostly useful from within "on_sel_grab"
        hooks.

    $oldtext = $term->selection ([$newtext])
        Return the current selection text and optionally replace it by
        $newtext.

    $term->overlay_simple ($x, $y, $text)
        Create a simple multi-line overlay box. See the next method for
        details.

    $term->overlay ($x, $y, $width, $height[, $rstyle[, $border]])
        Create a new (empty) overlay at the given position with the given
        width/height. $rstyle defines the initial rendition style (default:
        "OVERLAY_RSTYLE").

        If $border is 2 (default), then a decorative border will be put
        around the box.

        If either $x or $y is negative, then this is counted from the
        right/bottom side, respectively.

        This method returns an urxvt::overlay object. The overlay will be
        visible as long as the perl object is referenced.

        The methods currently supported on "urxvt::overlay" objects are:

        $overlay->set ($x, $y, $text, $rend)
            Similar to "$term->ROW_t" and "$term->ROW_r" in that it puts
            text in rxvt-unicode's special encoding and an array of
            rendition values at a specific position inside the overlay.

        $overlay->hide
            If visible, hide the overlay, but do not destroy it.

        $overlay->show
            If hidden, display the overlay again.

    $popup = $term->popup ($event)
        Creates a new "urxvt::popup" object that implements a popup menu.
        The $event *must* be the event causing the menu to pop up (a button
        event, currently).

    $cellwidth = $term->strwidth ($string)
        Returns the number of screen-cells this string would need. Correctly
        accounts for wide and combining characters.

    $octets = $term->locale_encode ($string)
        Convert the given text string into the corresponding locale
        encoding.

    $string = $term->locale_decode ($octets)
        Convert the given locale-encoded octets into a perl string.

    $term->scr_xor_span ($beg_row, $beg_col, $end_row, $end_col[, $rstyle])
        XORs the rendition values in the given span with the provided value
        (default: "RS_RVid"), which *MUST NOT* contain font styles. Useful
        in refresh hooks to provide effects similar to the selection.

    $term->scr_xor_rect ($beg_row, $beg_col, $end_row, $end_col[, $rstyle1[,
    $rstyle2]])
        Similar to "scr_xor_span", but xors a rectangle instead. Trailing
        whitespace will additionally be xored with the $rstyle2, which
        defaults to "RS_RVid | RS_Uline", which removes reverse video again
        and underlines it instead. Both styles *MUST NOT* contain font
        styles.

    $term->scr_bell
        Ring the bell!

    $term->scr_add_lines ($string)
        Write the given text string to the screen, as if output by the
        application running inside the terminal. It may not contain command
        sequences (escape codes), but is free to use line feeds, carriage
        returns and tabs. The string is a normal text string, not in
        locale-dependent encoding.

        Normally its not a good idea to use this function, as programs might
        be confused by changes in cursor position or scrolling. Its useful
        inside a "on_add_lines" hook, though.

    $term->scr_change_screen ($screen)
        Switch to given screen - 0 primary, 1 secondary.

    $term->cmd_parse ($octets)
        Similar to "scr_add_lines", but the argument must be in the
        locale-specific encoding of the terminal and can contain command
        sequences (escape codes) that will be interpreted.

    $term->tt_write ($octets)
        Write the octets given in $data to the tty (i.e. as program input).
        To pass characters instead of octets, you should convert your
        strings first to the locale-specific encoding using
        "$term->locale_encode".

    $old_events = $term->pty_ev_events ([$new_events])
        Replaces the event mask of the pty watcher by the given event mask.
        Can be used to suppress input and output handling to the pty/tty.
        See the description of "urxvt::timer->events". Make sure to always
        restore the previous value.

    $fd = $term->pty_fd
        Returns the master file descriptor for the pty in use, or -1 if no
        pty is used.

    $windowid = $term->parent
        Return the window id of the toplevel window.

    $windowid = $term->vt
        Return the window id of the terminal window.

    $term->vt_emask_add ($x_event_mask)
        Adds the specified events to the vt event mask. Useful e.g. when you
        want to receive pointer events all the times:

           $term->vt_emask_add (urxvt::PointerMotionMask);

    $term->focus_in
    $term->focus_out
    $term->key_press ($state, $keycode[, $time])
    $term->key_release ($state, $keycode[, $time])
        Deliver various fake events to to terminal.

    $window_width = $term->width
    $window_height = $term->height
    $font_width = $term->fwidth
    $font_height = $term->fheight
    $font_ascent = $term->fbase
    $terminal_rows = $term->nrow
    $terminal_columns = $term->ncol
    $has_focus = $term->focus
    $is_mapped = $term->mapped
    $max_scrollback = $term->saveLines
    $nrow_plus_saveLines = $term->total_rows
    $topmost_scrollback_row = $term->top_row
        Return various integers describing terminal characteristics.

    $x_display = $term->display_id
        Return the DISPLAY used by rxvt-unicode.

    $lc_ctype = $term->locale
        Returns the LC_CTYPE category string used by this rxvt-unicode.

    $env = $term->env
        Returns a copy of the environment in effect for the terminal as a
        hashref similar to "\%ENV".

    @envv = $term->envv
        Returns the environment as array of strings of the form "VAR=VALUE".

    @argv = $term->argv
        Return the argument vector as this terminal, similar to @ARGV, but
        includes the program name as first element.

    $modifiermask = $term->ModLevel3Mask
    $modifiermask = $term->ModMetaMask
    $modifiermask = $term->ModNumLockMask
        Return the modifier masks corresponding to the "ISO Level 3 Shift"
        (often AltGr), the meta key (often Alt) and the num lock key, if
        applicable.

    $screen = $term->current_screen
        Returns the currently displayed screen (0 primary, 1 secondary).

    $cursor_is_hidden = $term->hidden_cursor
        Returns whether the cursor is currently hidden or not.

    $view_start = $term->view_start ([$newvalue])
        Returns the row number of the topmost displayed line. Maximum value
        is 0, which displays the normal terminal contents. Lower values
        scroll this many lines into the scrollback buffer.

    $term->want_refresh
        Requests a screen refresh. At the next opportunity, rxvt-unicode
        will compare the on-screen display with its stored representation.
        If they differ, it redraws the differences.

        Used after changing terminal contents to display them.

    $text = $term->ROW_t ($row_number[, $new_text[, $start_col]])
        Returns the text of the entire row with number $row_number. Row 0 is
        the topmost terminal line, row "$term->$ncol-1" is the bottommost
        terminal line. The scrollback buffer starts at line -1 and extends
        to line "-$term->nsaved". Nothing will be returned if a nonexistent
        line is requested.

        If $new_text is specified, it will replace characters in the current
        line, starting at column $start_col (default 0), which is useful to
        replace only parts of a line. The font index in the rendition will
        automatically be updated.

        $text is in a special encoding: tabs and wide characters that use
        more than one cell when displayed are padded with $urxvt::NOCHAR
        (chr 65535) characters. Characters with combining characters and
        other characters that do not fit into the normal tetx encoding will
        be replaced with characters in the private use area.

        You have to obey this encoding when changing text. The advantage is
        that "substr" and similar functions work on screen cells and not on
        characters.

        The methods "$term->special_encode" and "$term->special_decode" can
        be used to convert normal strings into this encoding and vice versa.

    $rend = $term->ROW_r ($row_number[, $new_rend[, $start_col]])
        Like "$term->ROW_t", but returns an arrayref with rendition bitsets.
        Rendition bitsets contain information about colour, font, font
        styles and similar information. See also "$term->ROW_t".

        When setting rendition, the font mask will be ignored.

        See the section on RENDITION, above.

    $length = $term->ROW_l ($row_number[, $new_length])
        Returns the number of screen cells that are in use ("the line
        length"). Unlike the urxvt core, this returns "$term->ncol" if the
        line is joined with the following one.

    $bool = $term->is_longer ($row_number)
        Returns true if the row is part of a multiple-row logical "line"
        (i.e. joined with the following row), which means all characters are
        in use and it is continued on the next row (and possibly a
        continuation of the previous row(s)).

    $line = $term->line ($row_number)
        Create and return a new "urxvt::line" object that stores information
        about the logical line that row $row_number is part of. It supports
        the following methods:

        $text = $line->t ([$new_text])
            Returns or replaces the full text of the line, similar to
            "ROW_t"

        $rend = $line->r ([$new_rend])
            Returns or replaces the full rendition array of the line,
            similar to "ROW_r"

        $length = $line->l
            Returns the length of the line in cells, similar to "ROW_l".

        $rownum = $line->beg
        $rownum = $line->end
            Return the row number of the first/last row of the line,
            respectively.

        $offset = $line->offset_of ($row, $col)
            Returns the character offset of the given row|col pair within
            the logical line. Works for rows outside the line, too, and
            returns corresponding offsets outside the string.

        ($row, $col) = $line->coord_of ($offset)
            Translates a string offset into terminal coordinates again.

    $text = $term->special_encode $string
        Converts a perl string into the special encoding used by
        rxvt-unicode, where one character corresponds to one screen cell.
        See "$term->ROW_t" for details.

    $string = $term->special_decode $text
        Converts rxvt-unicodes text representation into a perl string. See
        "$term->ROW_t" for details.

    $success = $term->grab_button ($button, $modifiermask[, $window =
    $term->vt])
    $term->ungrab_button ($button, $modifiermask[, $window = $term->vt])
        Register/unregister a synchronous button grab. See the XGrabButton
        manpage.

    $success = $term->grab ($eventtime[, $sync])
        Calls XGrabPointer and XGrabKeyboard in asynchronous (default) or
        synchronous ($sync is true). Also remembers the grab timestamp.

    $term->allow_events_async
        Calls XAllowEvents with AsyncBoth for the most recent grab.

    $term->allow_events_sync
        Calls XAllowEvents with SyncBoth for the most recent grab.

    $term->allow_events_replay
        Calls XAllowEvents with both ReplayPointer and ReplayKeyboard for
        the most recent grab.

    $term->ungrab
        Calls XUngrab for the most recent grab. Is called automatically on
        evaluation errors, as it is better to lose the grab in the error
        case as the session.

    $atom = $term->XInternAtom ($atom_name[, $only_if_exists])
    $atom_name = $term->XGetAtomName ($atom)
    @atoms = $term->XListProperties ($window)
    ($type,$format,$octets) = $term->XGetWindowProperty ($window, $property)
    $term->XChangeWindowProperty ($window, $property, $type, $format,
    $octets)
    $term->XDeleteProperty ($window, $property)
    $window = $term->DefaultRootWindow
    $term->XReparentWindow ($window, $parent, [$x, $y])
    $term->XMapWindow ($window)
    $term->XUnmapWindow ($window)
    $term->XMoveResizeWindow ($window, $x, $y, $width, $height)
    ($x, $y, $child_window) = $term->XTranslateCoordinates ($src, $dst, $x,
    $y)
    $term->XChangeInput ($window, $add_events[, $del_events])
        Various X or X-related functions. The $term object only serves as
        the source of the display, otherwise those functions map
        more-or-less directory onto the X functions of the same name.

  The "urxvt::popup" Class
    $popup->add_title ($title)
        Adds a non-clickable title to the popup.

    $popup->add_separator ([$sepchr])
        Creates a separator, optionally using the character given as
        $sepchr.

    $popup->add_button ($text, $cb)
        Adds a clickable button to the popup. $cb is called whenever it is
        selected.

    $popup->add_toggle ($text, $initial_value, $cb)
        Adds a toggle/checkbox item to the popup. The callback gets called
        whenever it gets toggled, with a boolean indicating its new value as
        its first argument.

    $popup->show
        Displays the popup (which is initially hidden).

  The "urxvt::timer" Class
    This class implements timer watchers/events. Time is represented as a
    fractional number of seconds since the epoch. Example:

       $term->{overlay} = $term->overlay (-1, 0, 8, 1, urxvt::OVERLAY_RSTYLE, 0);
       $term->{timer} = urxvt::timer
                        ->new
                        ->interval (1)
                        ->cb (sub {
                           $term->{overlay}->set (0, 0,
                              sprintf "%2d:%02d:%02d", (localtime urxvt::NOW)[2,1,0]);
                        });                                                                                                                                      

    $timer = new urxvt::timer
        Create a new timer object in started state. It is scheduled to fire
        immediately.

    $timer = $timer->cb (sub { my ($timer) = @_; ... })
        Set the callback to be called when the timer triggers.

    $tstamp = $timer->at
        Return the time this watcher will fire next.

    $timer = $timer->set ($tstamp)
        Set the time the event is generated to $tstamp.

    $timer = $timer->interval ($interval)
        Normally (and when $interval is 0), the timer will automatically
        stop after it has fired once. If $interval is non-zero, then the
        timer is automatically rescheduled at the given intervals.

    $timer = $timer->start
        Start the timer.

    $timer = $timer->start ($tstamp)
        Set the event trigger time to $tstamp and start the timer.

    $timer = $timer->after ($delay)
        Like "start", but sets the expiry timer to c<urxvt::NOW + $delay>.

    $timer = $timer->stop
        Stop the timer.

  The "urxvt::iow" Class
    This class implements io watchers/events. Example:

      $term->{socket} = ...
      $term->{iow} = urxvt::iow
                     ->new
                     ->fd (fileno $term->{socket})
                     ->events (urxvt::EVENT_READ)
                     ->start
                     ->cb (sub {
                       my ($iow, $revents) = @_;
                       # $revents must be 1 here, no need to check
                       sysread $term->{socket}, my $buf, 8192
                          or end-of-file;
                     });

    $iow = new urxvt::iow
        Create a new io watcher object in stopped state.

    $iow = $iow->cb (sub { my ($iow, $reventmask) = @_; ... })
        Set the callback to be called when io events are triggered.
        $reventmask is a bitset as described in the "events" method.

    $iow = $iow->fd ($fd)
        Set the file descriptor (not handle) to watch.

    $iow = $iow->events ($eventmask)
        Set the event mask to watch. The only allowed values are
        "urxvt::EVENT_READ" and "urxvt::EVENT_WRITE", which might be ORed
        together, or "urxvt::EVENT_NONE".

    $iow = $iow->start
        Start watching for requested events on the given handle.

    $iow = $iow->stop
        Stop watching for events on the given file handle.

  The "urxvt::iw" Class
    This class implements idle watchers, that get called automatically when
    the process is idle. They should return as fast as possible, after doing
    some useful work.

    $iw = new urxvt::iw
        Create a new idle watcher object in stopped state.

    $iw = $iw->cb (sub { my ($iw) = @_; ... })
        Set the callback to be called when the watcher triggers.

    $timer = $timer->start
        Start the watcher.

    $timer = $timer->stop
        Stop the watcher.

  The "urxvt::pw" Class
    This class implements process watchers. They create an event whenever a
    process exits, after which they stop automatically.

       my $pid = fork;
       ...
       $term->{pw} = urxvt::pw
                        ->new
                        ->start ($pid)
                        ->cb (sub {
                           my ($pw, $exit_status) = @_;
                           ...
                        });                                                                                                                                      

    $pw = new urxvt::pw
        Create a new process watcher in stopped state.

    $pw = $pw->cb (sub { my ($pw, $exit_status) = @_; ... })
        Set the callback to be called when the timer triggers.

    $pw = $timer->start ($pid)
        Tells the watcher to start watching for process $pid.

    $pw = $pw->stop
        Stop the watcher.

ENVIRONMENT
  URXVT_PERL_VERBOSITY
    This variable controls the verbosity level of the perl extension. Higher
    numbers indicate more verbose output.

    == 0 - fatal messages
    >= 3 - script loading and management
    >=10 - all called hooks
    >=11 - hook return values

AUTHOR
     Marc Lehmann <pcg@goof.com>
     http://software.schmorp.de/pkg/rxvt-unicode

