diff --git a/klippy/extras/gcode_shell_command.py b/klippy/extras/gcode_shell_command.py
new file mode 100644
index 000000000000..85b664bebcf6
--- /dev/null
+++ b/klippy/extras/gcode_shell_command.py
@@ -0,0 +1,94 @@
+# Run a shell command via gcode
+#
+# Copyright (C) 2019  Eric Callahan <arksine.code@gmail.com>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
+import os
+import shlex
+import subprocess
+
+
+class ShellCommand:
+    def __init__(self, config):
+        self.name = config.get_name().split()[-1]
+        self.printer = config.get_printer()
+        self.gcode = self.printer.lookup_object("gcode")
+        cmd = config.get("command")
+        cmd = os.path.expanduser(cmd)
+        self.command = shlex.split(cmd)
+        self.timeout = config.getfloat("timeout", 2.0, above=0.0)
+        self.verbose = config.getboolean("verbose", True)
+        self.proc_fd = None
+        self.partial_output = ""
+        self.gcode.register_mux_command(
+            "RUN_SHELL_COMMAND",
+            "CMD",
+            self.name,
+            self.cmd_RUN_SHELL_COMMAND,
+            desc=self.cmd_RUN_SHELL_COMMAND_help,
+        )
+
+    def _process_output(self, eventime):
+        if self.proc_fd is None:
+            return
+        try:
+            data = os.read(self.proc_fd, 4096)
+        except Exception:
+            pass
+        data = self.partial_output + data.decode()
+        if "\n" not in data:
+            self.partial_output = data
+            return
+        elif data[-1] != "\n":
+            split = data.rfind("\n") + 1
+            self.partial_output = data[split:]
+            data = data[:split]
+        else:
+            self.partial_output = ""
+        self.gcode.respond_info(data)
+
+    cmd_RUN_SHELL_COMMAND_help = "Run a linux shell command"
+
+    def cmd_RUN_SHELL_COMMAND(self, params):
+        gcode_params = params.get("PARAMS", "")
+        gcode_params = shlex.split(gcode_params)
+        reactor = self.printer.get_reactor()
+        try:
+            proc = subprocess.Popen(
+                self.command + gcode_params,
+                stdout=subprocess.PIPE,
+                stderr=subprocess.STDOUT,
+            )
+        except Exception:
+            logging.exception("shell_command: Command {%s} failed" % (self.name))
+            raise self.gcode.error("Error running command {%s}" % (self.name))
+        if self.verbose:
+            self.proc_fd = proc.stdout.fileno()
+            self.gcode.respond_info("Running Command {%s}...:" % (self.name))
+            hdl = reactor.register_fd(self.proc_fd, self._process_output)
+        eventtime = reactor.monotonic()
+        endtime = eventtime + self.timeout
+        complete = False
+        while eventtime < endtime:
+            eventtime = reactor.pause(eventtime + 0.05)
+            if proc.poll() is not None:
+                complete = True
+                break
+        if not complete:
+            proc.terminate()
+        if self.verbose:
+            if self.partial_output:
+                self.gcode.respond_info(self.partial_output)
+                self.partial_output = ""
+            if complete:
+                msg = "Command {%s} finished\n" % (self.name)
+            else:
+                msg = "Command {%s} timed out" % (self.name)
+            self.gcode.respond_info(msg)
+            reactor.unregister_fd(hdl)
+            self.proc_fd = None
+
+
+def load_config_prefix(config):
+    return ShellCommand(config)