rosshell repository

Repository Summary

Checkout URI https://gitlab.com/OvGU-ESS/rosshell.git
VCS Type git
VCS Version master
Last Updated 2015-09-14
Dev Status MAINTAINED
CI status No Continuous Integration
Released UNRELEASED
Tags No category tags.
Contributing Help Wanted (0)
Good First Issues (0)
Pull Requests to Review (0)

Packages

Name Version
rosshell 1.0.0

README

rosshell

Two simple nodes that can be used as mediators for shell commands.

Author: André Dietrich & Sebastian Zug
License: BSD
Source: https://gitlab.com/andre-dietrich/rosshell

1. Overview

This package provides the two nodes, that enable to run and interact with different non-ros-programs. rosshell can be used to start a program or any kind of shell-command. If some kind of interaction with the programs is required, use rosshellX to receive and send messages from stdin, stdout, and stderr.

2. Usage

The required commands are always defined as a string:

$ rosrun rosshell rosshell.py "command"

$ rosrun rosshell rosshellX.py "command"

have a look at the examples or at the included launch-files.

3. Examples

3.1 rosshell

This command is just used to generate some random noise ...

$ rosrun rosshell rosshell.py "aplay -c 2 -f S16_LE -r 44100 /dev/urandom"

Pipe the results of /dev/random into a text file ...

$ rosrun rosshell rosshell.py "cat /dev/random > test.txt"

or the some information about the current directory ...

$ rosrun rosshell rosshell.py "ls -Shal > test.txt"

3.2 rosshellX

This node is used if you require some interaction with stdin, stdout, and stderr.

rosshellX is by default subscribed to /rosshellX/stdin and publishes at topic /rosshellX/stdout and /rosshellX/stderr, all of type std_msgs/String.

3.2.1 Some basic calculations

bc is just a simple commandline-calculator

  1. open three shells

  2. start bc with the following command:

   $ rosrun rosshell rosshellX.py "bc"

  1. print the the results of bc stdout by running:
   $ rostopic echo /rosshellX/stdout

  1. and now, send some inputs like:
   $ rostopic pub /rosshellX/stdin std_msgs/String "99*99\n"
   $ rostopic pub /rosshellX/stdin std_msgs/String "sqrt(2.0)\n"
   $ rostopic pub /rosshellX/stdin std_msgs/String "33^3\n"
   $ rostopic pub /rosshellX/stdin std_msgs/String "quit\n"

  1. to interact a bit with stderr, simply subscribe for:
   $ rostopic echo /rosshellX/stderr

and publish some nonsense like

   $ rostopic pub /rosshellX/stdin std_msgs/String "wtf\n"

3.2.1 Additional functionality

To get some filesystem-information try:

$ rosrun rosshell rosshellX.py "ls -Shal"

or

$ rosrun rosshell rosshellX.py _command:="ls -Shal"

both are the same but you also have the possibility to change the command and topics, also within the launch-file, have a look at rosshellX.launch ...

<node pkg="rosshell" type="rosshellX.py" name="rosshellBC">
  <param name="command" type="String" value="bc" />
  <param name="stdout"  type="String" value="bc/stdout" />
  <param name="stdout"  type="String" value="bc/stderr" />
  <param name="stdin"   type="String" value="bc/stdin" />
</node>

4. Nodes

4.1 rosshell

Allows to run commands with no interaction possibilities.

4.2 rosshellX

Allows to run commands and enables an interaction over stdin and stdout.

4.2.1 Subscribed Topics

/rosshellX/stdin (std_msgs/String)

The standard topic for stdin.

4.2.2 Published Topics

/rosshellX/stdout (std_msgs/String)

The current line of the stdout.

/rosshellX/stderr (std_msgs/String)

The current line of the stderr.

4.2.3 Parameters

command (string, default: "")

Commands that will be executed.

stdout (string, default: /rosshellX/stdout)

Change the topic for stdout.

stdin (string, default: /rosshellX/stdin)

Change the topic for stdin.

stderr (string, default: /rosshellX/stderr)

Change the topic for stderr.

CONTRIBUTING

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