Monty Bytecode Interpreter using C
Dr. Ehoneah Obed
In order to practicalize our knowledge of data structures like stacks and queues in C language, we were tasked with building a C program that acts as a Monty bytecode interpreter.
What is the Monty Bytecode Interpreter
This is a C program that will take a file as an argument, open the file, and read the instructions in the file, line by line.
For each line read, the interpreter is supposed to execute the instructions on that line.
The Monty bytecode is made up of special instructions and each line contains no or just one instruction.
The instructions are in the form of various operations that can be performed on stacks or queues.
Hence, the interpreter reads each line and performs the specific operation on a given stack or queue.
How to implement the Monty bytecode interpreter
This looks very complex to implement, but we can break the whole project into simple parts that will make the implementation easier.
Below are the steps that I used to implement the interpreter.
1. Create a C program that accepts a file as an argument
To be able to do this, you need knowledge of command line arguments in C language (Argc and Argv). You can check out this live session that I held to get a better understanding of these.
Since the program needs to run with the name of a file as an argument, you would have to check if the end-user has provided a file or not.
Every C program has a minimum of one command line argument, which is the name of the program itself.
Your interpreter should therefore be expecting 2 arguments (the name of the program itself followed by the name or path to the file with the Monty bytecodes).
You, therefore, have to check if Argc is equal to 2 before you proceed with any other thing.
If it is more or less then you have to throw an error message because the person may be using the program wrongly.
2. Check if the file can be accessed and open the file
Once, the end user is using your program as it's supposed to be used based on the earlier discussion then we have to now shift our focus to the file that the person provided.
Remember that we expect the file to be a Monty bytecode file (ending with the extension ".m").
Before we even get into the file to check its content, we need to know where the file that has been provided is accessible. As in, if we have permission to open it in the first place.
There is a standard C function that allows you to check whether a file is accessible or not. Use that function to check if you can access it.
If you can't access it, then throw an error but if you can access it then move on to the next step.
3. Open the file
Now that you know that you can access the file, you can go ahead and open the file.
NB: This isn't completed yet but my tight schedules is preventing me from continuing with it. I will continue as soon as I get some free time for it. You can always connect with me on Twitter.
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Dr. Ehoneah Obed
Dr. Ehoneah Obed
Heya! One thing I love doing is helping people and I believe one of the key ways I do this is through sharing of my knowledge and personal experiences. I have therefore decided to use this platform to share my knowledge and experience to people who may decide to take the path that I have taken. So, the question is, what is this path? I am professionally trained as a pharmacist but I have been an ardent lover and user of various technologies. During my practice at a tertiary hospital in the Northern Region of Ghana, I discovered a number of pertinent health problems and how technology can be used to solve those problems. In my quest for finding ways to solve some of these health problems with technology, I discovered the field of digital health and how that is transforming the way healthcare is being delivered. I am so much interested in the field and look forward to building a career in digital health and hopefully starting a company (startup) in that field. To make this career transition, I have to pursue further education and I have come across several paths that can lead to that career goal of mine. I have therefore decided to explore almost all the options that I have. For further studies, some of the courses which I came across that can help me achieve that career goal include a masters program or PHD in any of the following: Digital Health, Health technology, Health Informatics, Information Technology, Computer Science and Computational Science. I have therefore started applying to various schools offering any of the programs above. In the time being, I decided to start learning more about emerging technologies and that led me to take a three months course in Amazon Web Services (AWS). I am currently an AWS Certified Cloud Practitioner. During the 3 months training that I undertook at Ghana Tech Lab, Accra, I was introduced to a lot of things which excited me the more. I came to realize the potential of things I could do if I had the right knowledge especially in software development. Prior to this time, I had taught myself a number programming languages, libraries and frameworks for web development. I could consider myself as a fullstack developer with knowledge in HTML, CSS, Javascript, PHP, MySQL, WordPress, React, Laravel, and Codeigniter. However, I practiced less and didn't feel confident enough about my knowledge. I just knew I needed more. More learning, more practice, more projects and more connections with people in the industry. I started taking the Odin project to become a better web developer and a few days into it, I came across the ALX Software Engineering programme for Africans. Once I realized it was free to join, I was going to do everything in my capacity to qualify for it. I discovered the programme about 3 days to the deadline for the May 2022 Cohort. I therefore, sat through that night to finish my application to ALX. Fortunately for me, I got accepted into the program and a new phase of my life has started. I am now a Software Engineering Student looking forward to building a career in digital health. I know that this is just the beginning. As part of this programme, we spend about 70 hours a week learning, practicing, completing projects and building new relationships with our peers. As part of this journey, I am going to use this platform to document what I learn and share my journey to becoming a Software Engineer with you. Therefore, anyone at all looking to transition from their current career to software engineering will find what I post here relevant. Also, if you are a self-taught developer or you are thinking of teaching yourself software development, then you will also enjoy the content I publish here. Throughout my short journey of life, I have realized that we tend to give up on things easily when there is no form of accountability. I am therefore by this platform signing a deal to become accountable to you through sharing with you whatever I learn. Do share your thoughts and comments with me whenever you come across any of my post so I can truly remain accountable to you and never give up on this new found dream of mine.