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+ros-update - Update system installed from vcs
+
+# Synopsis
+
+* **ros update** system [system ...]
+* **ros update** method [params ...]
+
+# Description
+
+system
+
+  : a name specifying a system.
+
+method
+
+  : currently supported method is `git`.
+
+# Update system
+
+When system are already installed and the system has `.git` in the system directory it invoke `git pull` and `ros install` the system.
+
+# SEE ALSO
+_ros_(1), _ros-install_(1)