diff --git a/src/os/exec/exec.go b/src/os/exec/exec.go
index 19c7e24..0c17b7a 100644
--- a/src/os/exec/exec.go
+++ b/src/os/exec/exec.go
@@ -369,6 +369,8 @@
 
 // Start starts the specified command but does not wait for it to complete.
 //
+// If Start returns successfully, the c.Process field will be set.
+//
 // The Wait method will return the exit code and release associated resources
 // once the command exits.
 func (c *Cmd) Start() error {