Global Variables in C

A global variable in C is declared outside all functions, usually at the top of the program. It is accessible throughout the entire program, including all functions.

Key Points:

1. Declaration:
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   int globalVar = 10; // Global variable

2. Accessing Global Variables:
   • Can be accessed and modified in any function.
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   void display() {
printf("%d", globalVar); // Access global variable
}

3. Scope:
   • Global variables are visible throughout the program, from the point of declaration to the end of the program.
4. Modifying Global Variables:
   • Can be modified inside functions without the need to pass them as parameters.
5. Best Practice:
   • Avoid overusing global variables as they can lead to code that’s hard to maintain and debug.

Example:

Global variables should be used carefully to avoid potential issues with code clarity and maintenance.