[systemd-devel] [PATCHv2] man: Add a note about what environment variables are available by default.

[Colin Guthrie]

This question was asked by a user trying to debug a problem with Java services
which required JAVA_HOME to be set.
---
v2 Change the word "set" to "inherited (from PID1)" for clarity as to their default values.

 man/systemd.exec.xml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index c0e1d86..53a6eaf 100644
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -77,6 +77,14 @@
                 configuration options are configured in the [Service],
                 [Socket], [Mount], or [Swap] sections, depending on the unit
                 type.</para>
+
+                <para>All processes are executed in a clean environment in
+                which only the TERM, PATH, USER, and HOME variables are
+                inherited (from PID1) by default. In order to set additional
+                variables, see the Environment= and EnvironmentFile= options
+                below. To specify variables globally, you can configure
+                DefaultEnvironment= in
+                <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
         </refsect1>
 
         <refsect1>
-- 
1.8.3.4