From 08a39c8207b72058debfcf3550f582477f733ee9 Mon Sep 17 00:00:00 2001
From: Jente Hidskes <dev@hjdskes.nl>
Date: Fri, 20 Dec 2019 16:37:07 +0100
Subject: [PATCH] Document environment variables

Fixes #93.
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 docs/env_vars.md | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 docs/env_vars.md

diff --git a/docs/env_vars.md b/docs/env_vars.md
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+# Environment variables
+
+Cage sets the following environment variables:
+
+* `DISPLAY`: if compiled with Xwayland support, this will be set to the name of
+  the X display used for Xwayland.
+* `WAYLAND_DISPLAY`: specifies the name of the Wayland display that Cage is
+  running on.
+
+The following environment variables can be used to configure behavior of
+libraries that Cage uses.  Effectively, these environment variables configure
+the Cage session.
+
+## XKB environment variables
+
+```
+XKB_DEFAULT_RULES
+XKB_DEFAULT_MODEL
+XKB_DEFAULT_LAYOUT
+XKB_DEFAULT_VARIANT
+XKB_DEFAULT_OPTIONS
+```
+
+These environment variables configure the XKB keyboard settings. See
+xkeyboard-config(7).
+
+## Wlroots environment variables
+
+* `DISPLAY`: if set probe X11 backend.
+* `WAYLAND_DISPLAY`, `_WAYLAND_DISPLAY`, `WAYLAND_SOCKET`: if set probe Wayland
+  backend.
+* `XCURSOR_PATH`: directory where xcursors are located.
+
+For a complete list of wlroots environment variables, see
+https://github.com/swaywm/wlroots/blob/master/docs/env_vars.md.