init: Implement 'exec' command.
(cherry-pick of d05ab3952ec0e38f33a0e80ce6b9eb45b0064ba4.)
Change-Id: Id6d9bb32e51a0ad090ed8240cc505dc45b57b35d
diff --git a/init/readme.txt b/init/readme.txt
index 0b43fd5..132a869 100644
--- a/init/readme.txt
+++ b/init/readme.txt
@@ -136,10 +136,14 @@
--------
exec <path> [ <argument> ]*
+ This command is not implemented.
+
+execonce <path> [ <argument> ]*
Fork and execute a program (<path>). This will block until
- the program completes execution. It is best to avoid exec
- as unlike the builtin commands, it runs the risk of getting
- init "stuck". (??? maybe there should be a timeout?)
+ the program completes execution. This command can be run at most
+ once during init's lifetime. Subsequent invocations are ignored.
+ It is best to avoid exec as unlike the builtin commands, it runs
+ the risk of getting init "stuck".
export <name> <value>
Set the environment variable <name> equal to <value> in the