What is rtop? It is not an acronym, it is named so because it is very similar to htop, a widely used system process monitor, named after its original creater - Hisham Muhammad. I decided to create rtop to exercise my c++ skills. In my effort, I have taken ideas from htop's user interface. Infact, rtop's interface looks exactly like htop's - no point trying to come up with usability aspects when the wide htop user base testifies to its excellent usability. I myself have enjoyed using it. Since my goal has been to exercise my c++ skills, I have built rtop from ground up guided by these requirements, its completely of my own design, which I have described is this design document
Currently, rtop can be installed on any machine running Ubuntu 16.04 LTS (Xenial). The installation instructions and a brief demo of rtop's capabilities are provided below
rtop has 3 major dependencies - Boost.Log library, pugixml library (an XML parser) and Ncurses library. One needs to install them (in no particular order) before compiling and running rtop. I will detail the dependencies installation followed by instructions on rtop compilation
Clone rtop into you desired folder
> git clone https://github.com/kasliwalr/rtop.git # this will create an rtop folder
> tree -L 1 ./ # displays contents of rtop folder in tree form
./
├── config
├── docs
├── include
├── LICENSE
├── README.md
└── src
Boost is a C++ library suite (much like standard template library) with frequent new releases. I have used release boost1.63.0.
- Download boost source code for v1.63.0 from sourceforge. Download the .tar.gz file. You could download it anywhere, I downloaded it to Downloads folder and extracted it into boost1_63_0 folder
> cd ~/Downloads
> wget https://sourceforge.net/projects/boost/files/boost/1.63.0/boost_1_63_0.tar.gz
> tar -xvf boost_1_63_0.tar.gz # creates boost_1_63_0 folder and extracts contents into it
> cd boost_1_63_0
- Install Boost.Log binary. Detailed information can be found at the Boost's Getting started on Unix variants guide.
The boost_1_63_0 folder contents look like so
> tree -L 1 ./
./
├── boost
├── boost-build.jam
├── boostcpp.jam
├── boost.css
├── boost.png
├── bootstrap.bat
├── bootstrap.sh
├── doc
├── index.htm
├── index.html
├── INSTALL
├── Jamroot
├── libs
├── LICENSE_1_0.txt
├── more
├── README.md
├── rst.css
├── status
└── tools
We need to run the bootstrap.sh script. Since, we don't want to install all packages (takes a long time), we invoke the following command
> ./bootstrap.sh --with-libraries=log # root privilige is required to install in /usr/local. only installs Boost.Log
> sudo ./b2 install
This may take 5-10 minutes. So be prepared to wait a while. You can verify installation by checking /usr/local/lib, in there you should find libboost_log.so and some other boost libraries as well which are dependencies of Boost.Log.
NCurses is a library used for building text user interfaces on Unix systems. It talks to the terminal emulators (your typical linux terminals) on behalf of the application - using its API, it becomes easy to program for capturing keyboard input and sending output to the terminal. Ncurses is distributed as debian package, so we use apt-get facility
> sudo apt-get install libncurses5-dev libncursesw5-dev
pugixml is an XML file parsing library. We use xml files to configure our user interface and system interface, hence the need to use it.
- Download pugixml for linux from pugixml's git repo into libs subfolder of rtop folder and extract contents into pugixml-1.9 subfolder of libs
> cd rtop # navigate to rtop folder
> mkdir libs
> cd libs
> wget http://github.com/zeux/pugixml/releases/download/v1.9/pugixml-1.9.tar.gz
> tar -xvf pugixml-1.9.tar.gz # will automatically create pugixml-1.9 folder
- Modify pugixml source code. This step is required
> cd pugixml-1.9/src
> ls
pugiconfig.hpp pugixml.cpp pugixml.hpp
Open pugiconfig.hpp in your favourite editor, and uncomment line 44. The code should look like so
43 // Uncomment this to switch to header-only version
44 #define PUGIXML_HEADER_ONLY
Create a folder in rtop to hold the executable, call it bin
> cd rtop
> mkdir bin
> tree -L 1 ./
.
├── bin
├── config
├── docs
├── include
├── libs
├── LICENSE
├── README.md
└── src
Now navigate to src subfolder of rtop folder and invoke the Makefile to build the binary
> cd src
> ls
Makefile rtop_v0_1.cpp
> make -B # invoke make, it will read the accompanying Makefile, compile code and store executable in bin
Note that I am using c++11 flag with gcc version later than 5.4.0. The compiler will generate some warnings, this is ok, it does not create any issues. This warning will be eliminated in future revisions.
The application is started by opening a terminal window. Navigate to rtop folder on your computer, and locate the binary in bin subfolder. Invoke the executable as follows
> pwd
location_of_rtop/rtop/bin
> ./rtop_v0_1 ../config/CONFIGv0_1.xml # the config file is a required parameter
This should start the application, which should show the following view
The image is showing 3 columns for process id, parent process id and cmdline string for invoking the process. This is the default, as we see below we can change it.
You can scroll up and down the list using the ↑ or ↓ keys.
You can add more properties to view. To accomplish this, navigate to process settings view by pressing F2. In this view you see two columns for active properties and all properties. You could navigate between the two using ← and → keys. Whatever is in the active properties column will be visible in the process view.
In this demo, we add UTIME (user time) property to all properties. We navigate to all properties, scroll down using ↓ to UTIME, press ENTER to select it, its color will change to orange/yellow from blue. Now pressing the ← will move it to below the currently selected property in active properties. So UTIME goes below...Note that order of properties in active properties (top -> down) corresponding to column order in process view (left -> right)
Now to view the results of your actions, press ESC to return back to process view
To add another property, go back to process setting view by pressing F2. You could also delete properties from active properties column, or rearrange the order of items.
In this demo, the PPID (parent process id) was selected, and Del was pressed to remove it. Then STIME (system time property) is added to active properties column, since we want STIME to come after UTIME, we press ENTER (indicated by organe color) to select it for editing, and then press ↓ to move it below UTIME. Pressing ENTER again, releases the edit mode. Navigate back to process view mode (press ESC) to view the results. Here, we have properties displayed in desired order.
Rishabh Kasliwal