X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=docs%2Fipc.html;h=350483e33f37c8463906ac6da522aa4867504de3;hb=88d9e82dc03f7e7abc585ee5f6752b23171ad834;hp=f2ecf73a7c4534dd31167908f59b7f299583f550;hpb=fecded17e62e3adeb787630fccc15f53db25b8d1;p=i3%2Fi3.github.io diff --git a/docs/ipc.html b/docs/ipc.html index f2ecf73..350483e 100644 --- a/docs/ipc.html +++ b/docs/ipc.html @@ -2,15 +2,15 @@ "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> - + - + i3: IPC interface (interprocess communication) @@ -22,8 +22,9 @@ window.onload = function(){asciidoc.footnotes(); asciidoc.toc(2);}
@@ -31,7 +32,7 @@ window.onload = function(){asciidoc.footnotes(); asciidoc.toc(2);}

IPC interface (interprocess communication)

Michael Stapelberg
<michael@i3wm.org>
-October 2012 +September 2017
Table of Contents
@@ -91,85 +92,94 @@ they are in native byte order).

The magic string currently is "i3-ipc" and will only be changed when a change in the IPC API is done which breaks compatibility (we hope that we don’t need to do that).

-

Currently implemented message types are the following:

-
-
-COMMAND (0) -
-
-

- The payload of the message is a command for i3 (like the commands you - can bind to keys in the configuration file) and will be executed - directly after receiving it. -

-
-
-GET_WORKSPACES (1) -
-
-

- Gets the current workspaces. The reply will be a JSON-encoded list of - workspaces (see the reply section). -

-
-
-SUBSCRIBE (2) -
-
-

- Subscribes your connection to certain events. See [events] for a - description of this message and the concept of events. -

-
-
-GET_OUTPUTS (3) -
-
-

- Gets the current outputs. The reply will be a JSON-encoded list of outputs - (see the reply section). -

-
-
-GET_TREE (4) -
-
-

- Gets the layout tree. i3 uses a tree as data structure which includes - every container. The reply will be the JSON-encoded tree (see the reply - section). -

-
-
-GET_MARKS (5) -
-
-

- Gets a list of marks (identifiers for containers to easily jump to them - later). The reply will be a JSON-encoded list of window marks (see - reply section). -

-
-
-GET_BAR_CONFIG (6) -
-
-

- Gets the configuration (as JSON map) of the workspace bar with the - given ID. If no ID is provided, an array with all configured bar IDs is - returned instead. -

-
-
-GET_VERSION (7) -
-
-

- Gets the version of i3. The reply will be a JSON-encoded dictionary - with the major, minor, patch and human-readable version. -

-
-
+
+ + +++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
Table 1. Currently implemented message types
Type (numeric) Type (name) Reply type Purpose

0

RUN_COMMAND

COMMAND

Run the payload as an i3 command (like the commands you can bind to keys).

1

GET_WORKSPACES

WORKSPACES

Get the list of current workspaces.

2

SUBSCRIBE

SUBSCRIBE

Subscribe this IPC connection to the event types specified in the message payload. See [events].

3

GET_OUTPUTS

OUTPUTS

Get the list of current outputs.

4

GET_TREE

TREE

Get the i3 layout tree.

5

GET_MARKS

MARKS

Gets the names of all currently set marks.

6

GET_BAR_CONFIG

BAR_CONFIG

Gets the specified bar configuration or the names of all bar configurations if payload is empty.

7

GET_VERSION

VERSION

Gets the i3 version.

8

GET_BINDING_MODES

BINDING_MODES

Gets the names of all currently configured binding modes.

9

GET_CONFIG

CONFIG

Returns the last loaded i3 config.

10

SEND_TICK

TICK

Sends a tick event with the specified payload.

+

So, a typical message could look like this:

@@ -216,7 +226,7 @@ COMMAND (0)

- Confirmation/Error code for the COMMAND message. + Confirmation/Error code for the RUN_COMMAND message.

@@ -275,16 +285,41 @@ VERSION (7) Reply to the GET_VERSION message.

+
+BINDING_MODES (8) +
+
+

+ Reply to the GET_BINDING_MODES message. +

+
+
+GET_CONFIG (9) +
+
+

+ Reply to the GET_CONFIG message. +

+
+
+TICK (10) +
+
+

+ Reply to the SEND_TICK message. +

+

3.2. COMMAND reply

-

The reply consists of a single serialized map. At the moment, the only -property is success (bool), but this will be expanded in future versions.

+

The reply consists of a list of serialized maps for each command that was +parsed. Each has the property success (bool) and may also include a +human-readable error message in the property error (string).

Example:

-
{ "success": true }
+
[{ "success": true }]
@@ -298,7 +333,7 @@ num (integer)

The logical number of the workspace. Corresponds to the command - to switch to this workspace. + to switch to this workspace. For named workspaces, this will be -1.

@@ -422,12 +457,20 @@ active (boolean)

-current_workspace (integer) +primary (boolean)

- The current workspace which is visible on this output. null if the - output is not active. + Whether this output is currently the primary output. +

+
+
+current_workspace (string) +
+
+

+ The name of the current workspace that is visible on this output. null if + the output is not active.

@@ -447,7 +490,7 @@ rect (map) { "name": "LVDS1", "active": true, - "current_workspace": 4, + "current_workspace": "4", "rect": { "x": 0, "y": 0, @@ -458,13 +501,13 @@ rect (map) { "name": "VGA1", "active": true, - "current_workspace": 1, + "current_workspace": "1", "rect": { "x": 1280, "y": 0, "width": 1280, "height": 1024 - }, + } } ]
@@ -494,15 +537,26 @@ name (string) The internal name of this container. For all containers which are part of the tree structure down to the workspace contents, this is set to a nice human-readable name of the container. + For containers that have an X11 window, the content is the title + (_NET_WM_NAME property) of that window. For all other containers, the content is not defined (yet).

+type (string) +
+
+

+ Type of this container. Can be one of "root", "output", "con", + "floating_con", "workspace" or "dockarea". +

+
+
border (string)

- Can be either "normal", "none" or "1pixel", dependending on the + Can be either "normal", "none" or "pixel", depending on the container’s border style.

@@ -572,6 +626,16 @@ window_rect (map)

+deco_rect (map) +
+
+

+ The coordinates of the window decoration inside its container. These + coordinates are relative to the container and do not include the actual + client window. +

+
+
geometry (map)
@@ -596,7 +660,10 @@ urgent (bool)

- Whether this container (window or workspace) has the urgency hint set. + Whether this container (window, split container, floating container or + workspace) has the urgency hint set, directly or indirectly. All parent + containers up until the workspace container will be marked urgent if they + have at least one urgent child.

@@ -607,6 +674,34 @@ focused (bool) Whether this container is currently focused.

+
+focus (array of integer) +
+
+

+ List of child node IDs (see nodes, floating_nodes and id) in focus + order. Traversing the tree by following the first entry in this array + will result in eventually reaching the one node with focused set to + true. +

+
+
+nodes (array of node) +
+
+

+ The tiling (i.e. non-floating) child containers of this node. +

+
+
+floating_nodes (array of node) +
+
+

+ The floating child containers of this node. Only non-empty on nodes with + type workspace. +

+

Please note that in the following example, I have left out some keys/values which are not relevant for the type of the node. Otherwise, the example would @@ -707,7 +802,7 @@ VGA1 "y": 0, "width": 1280, "height": 0 - }, + } }, { @@ -872,6 +967,14 @@ workspace_buttons (boolean)

+binding_mode_indicator (boolean) +
+
+

+ Display the mode indicator or not? Defaults to true. +

+
+
verbose (boolean)
@@ -916,44 +1019,78 @@ separator

-focused_workspace_text/focused_workspace_bg +focused_background

- Text color/background color for a workspace button when the workspace + Background color of the bar on the currently focused monitor output. +

+
+
+focused_statusline +
+
+

+ Text color to be used for the statusline on the currently focused + monitor output. +

+
+
+focused_separator +
+
+

+ Text color to be used for the separator on the currently focused + monitor output. +

+
+
+focused_workspace_text/focused_workspace_bg/focused_workspace_border +
+
+

+ Text/background/border color for a workspace button when the workspace has focus.

-active_workspace_text/active_workspace_bg +active_workspace_text/active_workspace_bg/active_workspace_border

- Text color/background color for a workspace button when the workspace + Text/background/border color for a workspace button when the workspace is active (visible) on some output, but the focus is on another one. You can only tell this apart from the focused workspace when you are using multiple monitors.

-inactive_workspace_text/inactive_workspace_bg +inactive_workspace_text/inactive_workspace_bg/inactive_workspace_border

- Text color/background color for a workspace button when the workspace + Text/background/border color for a workspace button when the workspace does not have focus and is not active (visible) on any output. This will be the case for most workspaces.

-urgent_workspace_text/urgent_workspace_bar +urgent_workspace_text/urgent_workspace_bg/urgent_workspace_border

- Text color/background color for workspaces which contain at least one + Text/background/border color for workspaces which contain at least one window with the urgency hint set.

+
+binding_mode_text/binding_mode_bg/binding_mode_border +
+
+

+ Text/background/border color for the binding mode indicator. +

+

Example of configured bars:

@@ -970,6 +1107,7 @@ urgent_workspace_text/urgent_workspace_bar "status_command": "i3status", "font": "-misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1", "workspace_buttons": true, + "binding_mode_indicator": true, "verbose": false, "colors": { "background": "#c0c0c0", @@ -1022,18 +1160,59 @@ human_readable (string) this is what i3 --version displays, too).

+
+loaded_config_file_name (string) +
+
+

+ The current config path. +

+

Example:

{
    "human_readable" : "4.2-169-gf80b877 (2012-08-05, branch \"next\")",
+   "loaded_config_file_name" : "/home/hwangcc23/.i3/config",
    "minor" : 2,
    "patch" : 0,
    "major" : 4
 }
+
+

3.10. BINDING_MODES reply

+

The reply consists of an array of all currently configured binding modes.

+

Example:

+
+
+
["default", "resize"]
+
+
+
+

3.11. CONFIG reply

+

The config reply is a map which currently only contains the "config" member, +which is a string containing the config file as loaded by i3 most recently.

+

Example:

+
+
+
{ "config": "font pango:monospace 8\nbindsym Mod4+q exit\n" }
+
+
+
+

3.12. TICK reply

+

The reply is a map containing the "success" member. After the reply was +received, the tick event has been written to all IPC connections which subscribe +to tick events. UNIX sockets are usually buffered, but you can be certain that +once you receive the tick event you just triggered, you must have received all +events generated prior to the SEND_TICK message (happened-before relation).

+

Example:

+
+
+
{ "success": true }
+
+
@@ -1059,7 +1238,7 @@ you can register to an event.

type: SUBSCRIBE
-payload: [ "workspace", "focus" ]
+payload: [ "workspace", "output" ]
@@ -1100,7 +1279,8 @@ window (3)

Sent when a client’s window is successfully reparented (that is when i3 - has finished fitting it into a container). + has finished fitting it into a container), when a window received input + focus or when certain properties of the window have changed.

@@ -1109,7 +1289,34 @@ barconfig_update (4)

Sent when the hidden_state or mode field in the barconfig of any bar - instance was updated. + instance was updated and when the config is reloaded. +

+
+
+binding (5) +
+
+

+ Sent when a configured command binding is triggered with the keyboard or + mouse +

+
+
+shutdown (6) +
+
+

+ Sent when the ipc shuts down because of a restart or exit by user command +

+
+
+tick (7) +
+
+

+ Sent when the ipc client subscribes to the tick event (with "first": + true) or when any ipc client sends a SEND_TICK message (with "first": + false).

@@ -1136,14 +1343,15 @@ if ($is_event) {

4.3. workspace event

This event consists of a single serialized map containing a property change (string) which indicates the type of the change ("focus", "init", -"empty", "urgent").

-

Moreover, when the change is "focus", an old (object) and a current -(object) properties will be present with the previous and current -workspace respectively. When the first switch occurs (when i3 focuses -the workspace visible at the beginning) there is no previous -workspace, and the old property will be set to null. Also note -that if the previous is empty it will get destroyed when switching, -but will still be present in the "old" property.

+"empty", "urgent", "reload", "rename", "restored", "move"). A +current (object) property will be present with the affected workspace +whenever the type of event affects a workspace (otherwise, it will be +null).

+

When the change is "focus", an old (object) property will be present with the +previous workspace. When the first switch occurs (when i3 focuses the +workspace visible at the beginning) there is no previous workspace, and the +old property will be set to null. Also note that if the previous is empty +it will get destroyed when switching, but will still be present in the "old" +property.

Example:

@@ -1151,12 +1359,12 @@ but will still be present in the "old" property.

"change": "focus", "current": { "id": 28489712, - "type":4, + "type": "workspace", ... } "old": { "id": 28489715, - "type": 4, + "type": "workspace", ... } } @@ -1178,23 +1386,73 @@ but will still be present in the "old" property.

This event consists of a single serialized map containing a property change (string) which holds the name of current mode in use. The name is the same as specified in config when creating a mode. The default -mode is simply named default.

+mode is simply named default. It contains a second property, pango_markup, which +defines whether pango markup shall be used for displaying this mode.

Example:

-
{ "change": "default" }
+
{
+  "change": "default",
+  "pango_markup": true
+}

4.6. window event

This event consists of a single serialized map containing a property -change (string) which currently can indicate only that a new window -has been successfully reparented (the value will be "new").

+change (string) which indicates the type of the change

+

Additionally a container (object) field will be present, which consists -of the window’s parent container. Be aware that the container will hold -the initial name of the newly reparented window (e.g. if you run urxvt -with a shell that changes the title, you will still at this point get the -window title as "urxvt").

+of the window’s parent container. Be aware that for the "new" event, the +container will hold the initial name of the newly reparented window (e.g. +if you run urxvt with a shell that changes the title, you will still at +this point get the window title as "urxvt").

Example:

@@ -1202,7 +1460,7 @@ window title as "urxvt").

"change": "new", "container": { "id": 35569536, - "type": 2, + "type": "con", ... } } @@ -1211,18 +1469,112 @@ window title as "urxvt").

4.7. barconfig_update event

This event consists of a single serialized map reporting on options from the -barconfig of the specified bar_id that were updated in i3. The map always -consists of a property id (string), which specifies to which bar instance the -sent config update belongs, a property hidden_state (string), which indicates -the hidden_state of an i3bar instance, and a property mode (string), which -corresponds to the current mode.

+barconfig of the specified bar_id that were updated in i3. This event is the +same as a GET_BAR_CONFIG reply for the bar with the given id.

+ +
+

4.8. binding event

+

This event consists of a single serialized map reporting on the details of a +binding that ran a command because of user input. The change (string) field +indicates what sort of binding event was triggered (right now it will always be +"run" but may be expanded in the future).

+

The binding (object) field contains details about the binding that was run:

+
+
+command (string) +
+
+

+ The i3 command that is configured to run for this binding. +

+
+
+event_state_mask (array of strings) +
+
+

+ The group and modifier keys that were configured with this binding. +

+
+
+input_code (integer) +
+
+

+ If the binding was configured with bindcode, this will be the key code + that was given for the binding. If the binding is a mouse binding, it will be + the number of the mouse button that was pressed. Otherwise it will be 0. +

+
+
+symbol (string or null) +
+
+

+ If this is a keyboard binding that was configured with bindsym, this + field will contain the given symbol. Otherwise it will be null. +

+
+
+input_type (string) +
+
+

+ This will be "keyboard" or "mouse" depending on whether or not this was + a keyboard or a mouse binding. +

+
+
+

Example:

+
+
+
{
+ "change": "run",
+ "binding": {
+  "command": "nop",
+  "event_state_mask": [
+    "shift",
+    "ctrl"
+  ],
+  "input_code": 0,
+  "symbol": "t",
+  "input_type": "keyboard"
+ }
+}
+
+
+
+

4.9. shutdown event

+

This event is triggered when the connection to the ipc is about to shutdown +because of a user action such as a restart or exit command. The change +(string) field indicates why the ipc is shutting down. It can be either +"restart" or "exit".

Example:

{
-    "id": "bar-0",
-    "hidden_state": "hide"
-    "mode": "hide"
+ "change": "restart"
+}
+
+
+
+

4.10. tick event

+

This event is triggered by a subscription to tick events or by a SEND_TICK +message.

+

Example (upon subscription):

+
+
+
{
+ "first": true,
+ "payload": ""
+}
+
+

Example (upon SEND_TICK with a payload of arbitrary string):

+
+
+
{
+ "first": false,
+ "payload": "arbitrary string"
 }
@@ -1239,26 +1591,83 @@ know):

C
+
-Ruby +C++ +
+
+
+
+
+Go +
+
+
+
+
+JavaScript +
+
+
+
+
+Lua
+
Perl
+
Python @@ -1267,24 +1676,58 @@ Python
-Go +Ruby
+
+
+Rust +
+
+
+
+
+OCaml +
+
+
@@ -1292,6 +1735,118 @@ Go +
+

6. Appendix A: Detecting byte order in memory-safe languages

+
+

Some programming languages such as Go don’t offer a way to serialize data in the +native byte order of the machine they’re running on without resorting to tricks +involving the unsafe package.

+

The following technique can be used (and will not be broken by changes to i3) to +detect the byte order i3 is using:

+
    +
  1. +

    +The byte order dependent fields of an IPC message are message type and + payload length. +

    +
      +
    • +

      +The message type RUN_COMMAND (0) is the same in big and little endian, so + we can use it in either byte order to elicit a reply from i3. +

      +
      • +
    • +

      +The payload length 65536 + 256 (0x00 01 01 00) is the same in big and + little endian, and also small enough to not worry about memory allocations + of that size. We must use payloads of length 65536 + 256 in every message + we send, so that i3 will be able to read the entire message regardless of + the byte order it uses. +

      +
      • +
    +
    2. +
  2. +

    +Send a big endian encoded message of type SUBSCRIBE (2) with payload [] + followed by 65536 + 256 - 2 SPACE (ASCII 0x20) bytes. +

    +
      +
    • +

      +If i3 is running in big endian, this message is treated as a noop, + resulting in a SUBSCRIBE reply with payload {"success":true} +
      [A small payload is important: that way, we circumvent dealing + with UNIX domain socket buffer sizes, whose size depends on the + implementation/operating system. Exhausting such a buffer results in an i3 + deadlock unless you concurrently read and write, which — depending on the + programming language — makes the technique much more complicated.]
      . +

      +
      • +
    • +

      +If i3 is running in little endian, this message is read in its entirety due + to the byte order independent payload length, then + silently + discarded due to the unknown message type. +

      +
      • +
    +
    3. +
  3. +

    +Send a byte order independent message, i.e. type RUN_COMMAND (0) with + payload nop byte order detection. padding:, padded to 65536 + 256 bytes + with a (ASCII 0x61) bytes. i3 will reply to this message with a reply of + type COMMAND (0). +

    +
      +
    • +

      +The human-readable prefix is in there to not confuse readers of the i3 log. +

      +
      • +
    • +

      +This messages serves as a synchronization primitive so that we know whether + i3 discarded the SUBSCRIBE message or didn’t answer it yet. +

      +
      • +
    +
    4. +
  4. +

    +Receive a message header from i3, decoding the message type as big endian. +

    +
      +
    • +

      +If the message’s reply type is COMMAND (0), i3 is running in little + endian (because the SUBSCRIBE message was discarded). Decode the message + payload length as little endian, receive the message payload. +

      +
      • +
    • +

      +If the message’s reply type is anything else, i3 is running in big endian + (because our big endian encoded SUBSCRIBE message was answered). Decode + the message payload length in big endian, receive the message + payload. Then, receive the pending COMMAND message reply in big endian. +

      +
      • +
    +
    5. +
  5. +

    +From here on out, send/receive all messages using the detected byte order. +

    +
    6. +
+

Find an example implementation of this technique in +https://github.com/i3/go-i3/blob/master/byteorder.go

+
+