# Ros Launch Attribute

### Attribute

pkg="mypackage"

* Package of node.

type="nodetype"

* Node type. There must be a corresponding executable with the same name.

name="nodename"

* Node name. NOTE: name cannot contain a namespace. Use the ns attribute instead.

args="arg1 arg2 arg3"*(optional)*

* Pass arguments to node.

machine="machine-name"*(optional, see* [*\<machine>*](http://wiki.ros.org/roslaunch/XML/machine)*)*

* Launch node on designated machine.

respawn="true"*(optional, default: False)*

* Restart the node automatically if it quits.

respawn\_delay="30" *(optional, default 0)* New in ROS indigo

* If respawn is true, wait respawn\_delay seconds after the node failure is detected before attempting restart.

required="true"*(optional)*

* **ROS 0.10**: If node dies, kill entire roslaunch.

ns="foo"*(optional)*

* Start the node in the 'foo' namespace.

clear\_params="true|false"*(optional)*

* Delete all parameters in the node's private namespace before launch.

output="log|screen"*(optional)*

* If 'screen', stdout/stderr from the node will be sent to the screen. If 'log', the stdout/stderr output will be sent to a log file in $ROS\_HOME/log, and stderr will continue to be sent to screen. The default is 'log'.

cwd="ROS\_HOME|node"*(optional)*

* If 'node', the working directory of the node will be set to the same directory as the node's executable. In C Turtle, the default is 'ROS\_HOME'. In Box Turtle (ROS 1.0.x), the default is 'ros-root'. The use of 'ros-root' is deprecated in C Turtle.

launch-prefix="prefix arguments"*(optional)*

* Command/arguments to prepend to node's launch arguments. This is a powerful feature that enables you to enable gdb, valgrind, xterm, nice, or other handy tools. See [Roslaunch Nodes in Valgrind or GDB](http://wiki.ros.org/roslaunch/Tutorials/Roslaunch%20Nodes%20in%20Valgrind%20or%20GDB) for examples.
