OVERVIEW
COBOL is a high-level language. One must understand the way COBOL works. Computers only understand machine code, a binary stream of 0s and 1s. COBOL code must be converted into machine code using a compiler. Run the program source through a compiler. The compiler first checks for any syntax errors and then converts it into machine language. The compiler creates an output file which is known as load module. This output file contains executable code in the form of 0s and 1s.
Importance of COBOL
COBOL was the first widely used high-level programming language. It is an English-like language which is user friendly. All the instructions can be coded in simple English words.
COBOL is also used as a self-documenting language.
COBOL can handle huge data processing.
COBOL is compatible with its previous versions.
COBOL has effective error messages and so, resolution of bugs is easier.
Features of COBOL
Standard Language
COBOL is a standard language that can be compiled and executed on machines such as IBM AS/400, personal computers, etc.
Business Oriented
COBOL was designed for business-oriented applications related to financial domain, defense domain, etc. It can handle huge volumes of data because of its advanced file handling capabilities.
GET STARTED
To choose a Region follow the below step:
1. Sign in to the AWS Management Console.
2. Choose a service to go to that service's console.
3. In the navigation bar, choose the name of the currently displayed Region. Then choose the Region to which you want
to switch.
Step instructions for how to assess and monitor the health and proper function of the application:
1. Navigate to your Amazon EC2 console and verify that you're in the correct region.
2. Choose Instance and select your launched instance.
3. Select the server to display your metadata page and choose the Status checks tab at the bottom of the page to review if your status checks passed or failed.
To verify the installation, follow the below instructions
Step 1. Connect to SSH:
Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.
In the navigation pane, choose Instances.
Select the instance and choose Connect.
Choose SSH Client
Copy the SSH command and paste it into the terminal.
ssh ec2-user@publicIP -i [Path of key pair file]If it shows an access denied message run the following command, then run the above command again to connect via ssh.
chmod 400 [Path of key pair file]Once launched in the Amazon EC2 Service, please connect to the instance via an SSH client using the ec2-user with the key pair associated at launch. Once connected as the ec2-user user, you will be able to sudo to the root user
Step 2. Verify the installation
Follow the steps to verify the COBOL language installation
1. Login with ssh
2. Type the below command to check the version
cobc --version
How to use COBOL language in the terminal:
1. After connecting with ssh write the below command:
sudo vi test.cob3. Paste the following code into the file: :
IDENTIFICATION DIVISION.
PROGRAM-ID. HELLO-WORLD.
PROCEDURE DIVISION.
DISPLAY 'Hello, World!'.
STOP RUN.2. After that use the below command :
cobc -x test.cob3. Then run the below command :
./test
The output "Hello World" should appear in your terminal.
That's it! You have successfully printed "Hello, World!" using COBOL in the terminal.
To monitor and assess application functions:-
a. Navigate to your Amazon EC2 console and verify that you're in the correct region.
b. Choose Instances and select your launched instance.
c. Select the server to display your metadata page and choose the Status checks tab at the bottom of the page to review if your status checks passed or failed.
For detailed information on how to use this application please visit: https://www.tutorialspoint.com/cobol/index.htm
For detailed information about managing and requesting increased service please visit: https://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html
