C Cheatsheet

This cheatsheet covers the complete foundational toolkit for C programming:

Quick Start & Compilation

Data Types & Variables

Input / Output

Control Flow

Arrays

Strings

Pointers

Functions

Structures

File I/O

Preprocessor Directives

Command-Line Arguments

Memory Management

Quick Reference Tables

Quick Start & Compilation: Basic program execution, command-line arguments, and compiler warnings using gcc.

Data Types & Variables: Primitive types (int, char, float, double), sizing, ranges, and format specifiers.

Input / Output: Standard I/O handling via printf, scanf, fgets, and safe string handling.

Control Flow: Conditional logic (if-else, switch) and iteration (for, while, do-while loops).

Core Data Structures: Single/multi-dimensional arrays, strings, and standard library string manipulation functions (strlen, strcpy, strcmp, etc.).

Advanced Memory & Structure: Pointers, dereferencing, custom data structures (struct, typedef), and dynamic memory allocation (malloc, calloc, realloc, free).

File Handling & Preprocessors: Reading/writing files using file pointers (fopen, fprintf, fgets) and preprocessor directives like #define and macros.

Target Audience

This cheat sheet is useful for:

Students & Beginners: Individuals learning C programming who need a quick reference sheet for labs, homework, and coding assignments.

Exam & Viva Candidates: Students preparing for university practical exams or technical vivas requiring fast syntax revision.

Developers & Programmers: Professionals needing a handy, single-page summary to refresh memory on core C memory management, pointers, and format specifiers.