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alttab(1) -- the task switcher
==============================

## SYNOPSIS

`alttab` [`-w` <N>] [`-d` <N>] [`-sc` <N>] [`-mk` <str>] [`-kk` <str>] [`-bk` <str>] [`-pk` <str>] [`-nk` <str>] [`-mm` <N>] [`-bm` <N>] [`-t` <NxM>] [`-i` <NxM>] [`-vp` <str>] [`-p` <str>] [`-s` <N>] [`-theme` <name>] [`-bg` <color>] [`-fg` <color>] [`-frame` <color>] [`-bc` <color>] [`-bw` <N>] [`-font` <name>] [`-vertical`] [`-v`\|`-vv`]

## DESCRIPTION

The task switcher designed for minimalistic window managers or standalone X11 session.

Unlike task switchers integrated in most simple WMs,
`alttab` features visual interface and convenient
tactile behaviour, switching windows on releasing Alt key.

Being lightweight and depending only on core X11 libs, 
it still features customizable look and behaviour.

## OPTIONS

Most command line options have corresponding X resource, see doc/alttab.ad for example.

  * `-w` <NUMBER>:
    resource: alttab.windowmanager  
    default: autodetect, fallback to <3>

    Control how to obtain window list and set focus. <NUMBER> must be between 0 and 3:

      <0>: No WM, raw X.

      Set this value manually, as it's not autodetected. 
      Only top-level viewable children of root window are listed.
      Running **-w 0** under WM is discouraged: hidden windows or windows on another desktops will not be listed; instead, some strange windows may be included. 

      <1>: EWMH compatible.

      Compatible WM list is in [SEE ALSO] below. alttab functions in xmonad (EWMH must be
      allowed, details in doc/wm-setup.md), i3, evilwm, xfwm4, metacity, jwm, openbox, fluxbox,
      icewm, enlightenment, blackbox, aewm, fvwm, sawfish, bspwm.
      The following WMs support EWMH partially but work in **-w 1** mode too:
      dwm (issue #9), matchbox (issue #34), windowmaker (issue #9),
      xpra (issue #37), cwm (issue #35), ctwm (issue #39), lwm (issue #40),
      awesome (issue #41).

      <2>: Ratpoison.

      Alttab uses ratpoison own remote control capability. Additionally, alttab registers itself in its "unmanaged list" automatically.

      <3>: Ancient WM.

      Fallback, worse than <0>.
      Search for application windows at random nodes of window tree (WM is probably reparenting)
      and select only those with a name, including non-viewable (WM is probably iconifying).
      May cause lag.
      Tested in twm, flwm, wm2.

  * `-d` <NUMBER>:
    resource: alttab.desktops  
    default: <0>

    Show windows belonging to desktops (workspaces, groups). <NUMBER> must be between 0 and 3:

      <0>: Current desktop.

      This is default, although in non EWMH-compatible WM, except ratpoison, it's effectively the same as <1>.

      <1>: All desktops.

      <2>: All desktops, excluding special (-1) one.

      In various EWMH WM this desktop may be designed hidden
      or containing sticky windows. In i3, it's "scratchpad".

      <3>: All desktops, excluding current and special.

  * `-sc` <NUMBER>:
    resource: alttab.screens  
    default: <1>

    Show windows belonging to xrandr/xinerama screens. <NUMBER> must be 0 or 1:

      <0>: Current screen.

      As defined according to `-vp` <pointer> or `-vp` <focus>.

      <1>: All screens.

      This is default.

  * `-mk` <str>:
    resource: alttab.modifier.keysym  
    default: Alt_L

    Keysym of main modifier. String or number accepted.
    Suitable examples: Control_L, Super_L.

  * `-kk` <str>:
    resource: alttab.key.keysym  
    default: Tab

    Keysym of main key.
    For example, grave (aka tilde), Escape.

  * `-bk` <str>:
    resource: alttab.backscroll.keysym  
    default: any Shift, according to ShiftMask

    Keysym of backward scroll key.

  * `-pk` <str>:
    resource: alttab.prevkey.keysym  
    default: no key assigned

    Keysym of auxiliary 'previous' key.
    For example, Left, H.

  * `-nk` <str>:
    resource: alttab.nextkey.keysym  
    default: no key assigned

    Keysym of auxiliary 'next' key.
    For example, Right, L.

  * `-ck` <str>:
    resource: alttab.cancelkey.keysym  
    default: Escape

    Keysym of auxiliary 'cancel' key.

  * `-mm` <NUM>:
    resource: alttab.modifier.mask  

    OBSOLETED, guessed from -mk instead.

  * `-bm` <NUM>:
    resource: alttab.backscroll.mask  

    OBSOLETED, guessed from -bk instead.

  * `-t` <NNxMM>:
    resource: alttab.tile.geometry  
    default: <112x128>

    Size of a single tile (mini-window). If switcher doesn't fit the viewport (`-vp`), tile may be thinner.

  * `-i` <NNxMM>:
    resource: alttab.icon.geometry  
    default: <32x32>

    Size of icons.

  * `-vp` <str>:
    resource: alttab.viewport  
    default: <focus>

    Limit viewport for the switcher.
    The switcher always has variable size and position,
    but tries to never break out of `-vp` container,
    while `-p` specifies position relative to this container.
    Together these options allow for WM-independent multi-monitor support.
    Possible values for `-vp`:

      <focus>: in multihead configuration: the monitor which shows
      largest part of currently focused window. If this part is shared
      with other monitors, then the smallest of these monitors is choosen.
      In single head configuration: the geometry of default root window.

      <pointer>: the monitor which has mouse pointer, otherwise
      the same as <focus>.

      The "multihead" above means more than one active XRANDR output. 
      They are detected at runtime, so hopefully monitors
      may be attached/detached without restarting alttab.

      <total>: the geometry of default root window.

      If you specify this in tiling multihead configuration, then
      the switcher will be drawn relative to the entire combined screen,
      crossing monitors' borders.

      <WxH+X+Y>: Specific position relative to default root window.

      This allows for static manual bounding if XRANDR detection fails.
      Suppose X root window spans over two 2560х1440 monitors, 
      resulting in combined screen of 5120x1440 size. Then the switcher 
      may be positioned at the center of the right monitor 
      with -vp 2560x1440+2560+0 -p center.

  * `-p` <str>:
    resource: alttab.position  
    default: center

    Position of switcher: "center", "none" or specific position relative
    to upper left corner of viewport, in the form <+X+Y>.

  * `-s` <NUMBER>:
    resource: alttab.icon.source  
    default: 2

    Source of icons. <NUMBER> must be between 0 and 3:

      <0>: Use icons from X11 window attributes only.
      
      <1>: Load icon from file if not found in window attributes.

      Alttab searches for PNG and XPM icons in $XDG_DATA_DIRS and also under:  
  
      /usr/share/icons  
      /usr/local/share/icons  
      ~/.icons  
      ~/.local/share/icons  
  
      Directory structure should obey freedesktop standard, but desktop files are ignored,
      instead file name is expected to be equal to application class. 
      That is, if alttab doesn't recognize an icon for window of class foo,
      as obtained by 'xprop WM_CLASS', then just drop a 32x32 icon into
      /usr/local/share/icons/hicolor/32x32/apps/foo.png.
  
      Also, alttab scans for icons in legacy directories without freedesktop directory
      structure:  
  
      /usr/share/pixmaps  
      ~/.local/share/pixmaps  

      <2>: Prefer icon from file when it matches requested size better (see `-i` option).

      <3>: Use icons from files only.

  * `-theme` <name>:
    resource: alttab.theme  
    default: <hicolor>

    Desktop theme for application icons. Used when `-s` is 1, 2 or 3.

The following three options accept color names or <#rrggbb>. Special value <&#95;rnd_low> or <&#95;rnd_high> produce random color from lower or upper RGB space respectively.

  * `-bg` <color>:
    resource: alttab.background  
    default: <black>

    Tile background color.

  * `-fg` <color>:
    resource: alttab.foreground  
    default: <grey>

    Foreground color.

  * `-frame` <color>:
    resource: alttab.framecolor  
    default: <#a0abab>

    Color of frame around selected tile.

  * `-bc` <color>:
    resource: alttab.bordercolor  
    default: <black>

    Color of extra border around the entire switcher. This border may look redundant. Do not confuse with `-frame`.

  * `-bw` <N>:
    resource: alttab.borderwidth  
    default: <0> (no extra border)

    Width of extra border above.

  * `-font` <name>:
    resource: alttab.font  
    default: *xft:sans-10*

    Label font name in format: `xft:fontconfig_pattern`, like in emacs and rxvt. See [SEE ALSO] for fontconfig pattern. It's neither GTK font pattern nor legacy XLFD.

Your Xresources database probably already has \*background, \*foreground or \*font wildcard definitions, which alttab will obey. Precedence order (preferred first):

   alttab.font resource,  
   `-font` option,  
   wildcard resource like \*font in xfd: format.

  * `-vertical`:
    resource: alttab.vertical  
    default: no

    Vertical layout (experimental).

  * `-v`, `-vv`:
    resource: no  
    default: silent

    Verbosity.

  * `-h`:
    short help

##CAVEATS

Run alttab after WM, or autodetection will fail.

##AUTHOR

Copyright 2017-2021 Alexander Kulak `<sa-dev AT odd POINT systems>`.

##REPORTING BUGS

Please [report issues on github](https://github.com/sagb/alttab/issues).

##SEE ALSO

[EWMH compatible WM list](https://en.wikipedia.org/wiki/Extended_Window_Manager_Hints#List_of_window_managers_that_support_Extended_Window_Manager_Hints).

[Description of fontconfig pattern](https://www.freedesktop.org/software/fontconfig/fontconfig-user.html).

