Resources for CS 2040

Installing Ruby, C++

• Installing a virtual machine for building Ruby and C++ programs.
• Updated VM with a 25GB disk partition: https://msoe.box.com/s/okfriovylnn8amioso3r433rkkqj83tv
• The VM itself is at https://msoe.app.box.com/s/c95d29z6ke8glnxei769ctyrb52wts6c
• Note the ruby and irb commands work on this VM; CodeLite may not be configured for simple development of Ruby programs.
• The current version of g++ defaults to using the 2017 standard; that is, g++ xyz.cpp is equivalent to writing g++ --std=c++17 xyz.cpp

Additional resources for C++

• An Overview of the C++ Programming Language by Bjarne Stroustrup, the creator of C++.
• Replit C++ Environment: a simple way to run short C++ programs, especially if you are having problems on your computer.
• cplusplus.com: a great reference for C++. If you don't understand what this site is saying, review the relevant terms in the textbook; this site assumes readers generally understand C++.
• Caution! Stack Overflow (SO) is a dangerous resource for this course: many suggestions there do not apply to the type of C++ code you should be writing for CS 2040. On the other hand, SO at least generally contains factual information; there are high-profile sites that provide no additional information beyond what you can find explained more clearly in your textbook.

Fixing C++ Problems

• C++ Compiler errors and fixes
• Debugging 201: Debugging memory faults in C++ such as random runtime errors, segmentation faults, and even infinite loops.
• My program runs on my machine but not esubmit: This means you have a memory fault; see the previous bullet.
• How do I submit input to a running program on my machine? In the VM, press Control-D to mark the end of the input (end of file). You may need to press the Enter key after this.
• My program doesn't have any output in the VM. Try submitting to esubmit; it can happen that the VM breaks. If the program has output on esubmit but not the VM, the simple thing is to reinstall the VM. You can also ask your instructor for help on debugging the problem.

Virtual Machines (VMs) and Fixing VM Problems

• Using Codelite
• If opening files is not working in CodeLite:
  1. Right click on your project and select Settings...
  2. In the General group, scroll down to Working Directory and set it to $(WorkspacePath)/. Then, press the tab key.
  3. If you have not done so, select the Compiler tab and set C++ Compiler Options to -g;-O0;-Wall;-std=c++17. Again, press the tab key.
  4. You might go back and check the Working Directory in the General tab - it is very easy to not save your changes.
  5. Click OK
  You can now place the files in the top level directory of the workspace. That is, if your workspace is named myspace, put your files in the same folder that contains myspace.workspace.
• Setting up a git repository on your VM
• Fixing virtual machines (VMs) that are laggy or otherwise running slowly: Start by ensuring your laptop has sufficient battery power. Windows throttles the CPU on low power and this is very noticeable on a virtual machine. Next, check for any updates using Lenovo Commercial Vantage and Windows Update. Install all updates; this may require multiple reboots followed by more checks. Check that your Windows disk drive is no more than around 90% full; a very full drive impacts the memory management system. Finally, reboot your laptop if it has not been rebooted recently. This will eliminate any runaway processes.