Before we begin with our basic concepts of the C programming language let’s take a look at the C Program -Structure of a simple code for better understanding.
A C program consists of the following components−
- standard input-output library functions
- variables
- comments
- statements
- operators
- operands
- functions
Hello World Program
#include <stdio.h>
1. int main()
2. {
3. /* first program in C */
4. printf("Hell, World!");
5. return 0;
6. }
Description of the above code:
- here the first line of the code #include <stdio.h> is the standard input-output library. printf() function is defined in the stdio.h library file.
- int main() is the main function where the execution of the code begins.
- The opening curly brace { symbolizes the beginning of the block.
- The statement inside /*…*/ is the comment which is ignored by the compiler.
- The print() function prints the message “Hello World” on the output window/screen.
- The return 0 statement is the ending of the code, as well as returns the execution state of the OS.
- The closing curly brace } symbolizes the end of the block.
Compiling and Executing a C Program
Let us take a look at how to compile and run a program:
- If you are using a C code editor, you may directly click on the compile and run button resulting in the compilation of the program and an output will be generated on the screen.
- Otherwise, if you are using the command prompt then follow the below-given methods.
- open an editor and type your code in it
- save the file with the “.c” extension.
- open the command prompt go to the directory where you saved your c file
- type gcc filename.c -o filename and press enter.
Output
$ gcc filename.c -o filename
$ ./filename
Hello, World!Make sure the gcc compiler is in your path and that you are running it in the directory containing the source file filename.c.
Now you might have a good understanding of the C Program -Structure.
Note: Also read C Programming Language Overview C Programming Language
Staying up to the mark is what defines me. Hi all! I’m Rabecca Fatima a keen learner, great enthusiast, ready to take new challenges as stepping stones towards flying colors.