extern Keyword in C – Declaration, Definition, and Multi-File Programs

Posted on October 14, 2011June 24, 2026 by Sandeepa Nadahalli

The extern keyword in C declares that a variable or function exists — but is defined somewhere else. It tells the compiler “trust me, this symbol is defined in another translation unit; the linker will resolve it.” Understanding extern is essential for any multi-file C program, and confusing declaration with definition is one of the …

C Program to Demonstrate global and internal variables.

Posted on October 10, 2011 by Sandeepa Nadahalli

C Program to Demonstrate global and internal variables.When variable declared outside the all the blocks, they are called global variables, and they are initialized by the system. Variables declared within the functions are called as internal variables, the are locale to that function, and user only initialize the variable. Read more about C Programming Language …