Revamped environment variables again.

[nssm.git] / README.txt

diff --git a/README.txt b/README.txt
index ded8b7a..85bf62e 100644 (file)
--- a/README.txt
+++ b/README.txt
@@ -354,7 +354,33 @@ environment variables which will be added to the service's environment.
 Each entry in the list should be of the form KEY=VALUE.  It is possible to\r
 omit the VALUE but the = symbol is mandatory.\r
 \r
-srvany only supports AppEnvironment.\r
+Environment variables listed in both AppEnvironment and AppEnvironmentExtra\r
+are subject to normal expansion, so it is possible, for example, to update the\r
+system path by setting "PATH=C:\bin;%PATH%" in AppEnvironmentExtra.  Variables\r
+are expanded in the order in which they appear, so if you want to include the\r
+value of one variable in another variable you should declare the dependency\r
+first.\r
+\r
+Because variables defined in AppEnvironment override the existing\r
+environment it is not possible to refer to any variables which were previously\r
+defined.\r
+\r
+For example, the following AppEnvironment block:\r
+\r
+      PATH=C:\Windows\System32;C:\Windows\r
+      PATH=C:\bin;%PATH%\r
+\r
+Would result in a PATH of "C:\bin;C:\Windows\System32;C:\Windows" as expected.\r
+\r
+Whereas the following AppEnvironment block:\r
+\r
+      PATH=C:\bin;%PATH%\r
+\r
+Would result in a path containing only C:\bin and probably cause the\r
+application to fail to start.\r
+\r
+Most people will want to use AppEnvironmentExtra exclusively.  srvany only\r
+supports AppEnvironment.\r
 \r
 \r
 Managing services using the GUI\r