getchar and putchar in C — Character I/O That Actually Works
Learn how getchar and putchar work in C, why getchar returns int not char, how to use them to copy input, count characters, and avoid scanf’s buffer problems.
Read articleint main() vs void main() in C — Why the Return Type Matters
Learn why int main() is correct in C and void main() is not. Understand return values, EXIT_SUCCESS, argc/argv, and the two valid signatures for main.
Read articleOperator Precedence in C — The Bugs That Look Correct
Learn the C operator precedence rules that cause the most real bugs. Bitwise operators, ternary, sizeof, and pointer arithmetic traps explained with examples.
Read articleSignal Handling in C — SIGINT, SIGTERM, and Graceful Shutdown
Learn how to handle signals in C programs. Write signal handlers for SIGINT and SIGTERM, understand async-signal safety, and implement clean shutdown.
Read articleBinary File I/O in C — fread, fwrite, fseek, and ftell
Learn how to read and write binary files in C with fread, fwrite, fseek, and ftell. Covers struct serialization, file positions, and cross-platform pitfalls.
Read articleWriting a Hash Table in C from Scratch
Learn how to implement a hash table in C with separate chaining. Covers hash functions, collision handling, dynamic resizing, and deletion.
Read articleTwo’s Complement — Why -1 in Binary Looks Like 0xFFFFFFFF
Learn how two’s complement represents negative integers in C, why -1 is all ones in binary, how overflow works, and what this means for bit manipulation.
Read articleValgrind Basics — Finding Memory Leaks and Invalid Reads in C
Learn how to use Valgrind to find memory leaks, invalid reads, use-after-free bugs, and uninitialized memory in C programs. With real output examples.
Read articleHow qsort Works in C — Sorting Any Type with Function Pointers
Learn how to use qsort in C to sort integers, strings, structs, and custom types. Understand the comparator contract and common mistakes.
Read articleenum in C — Patterns, Sizes, and the Mistakes You’re Probably Making
Learn how C enums work, their size and underlying type, how to use them as flags, and the common pitfalls around assignment, comparison, and switch statements.
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