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C++ for C Developers

You already know most of C++. The syntax is nearly identical — what changes is the idioms. This path covers exactly the delta: what to drop, what to upgrade, and what stays the same.

The good news

C++ is a strict superset of most C. Your existing C code compiles as C++ with little or no modification. The transition is about learning C++ idioms — not relearning programming. A strong C developer can be productive in C++ within a week, and expert within a few months.

The key mindset shifts

In C you write	In C++ you write	Why
malloc/free	unique_ptr / make_unique	Automatic lifetime management eliminates most memory bugs
#define MAX 100	constexpr int MAX = 100;	Type-safe, scoped, debuggable
void* for generics	Templates	Type-safe generics with zero overhead
printf("%d", n)	std::cout << n or std::print("{}", n)	Type-safe I/O, no format string bugs
struct + function ptrs	Classes with virtual functions	Encapsulation + polymorphism built in
errno for errors	Exceptions or std::expected	Cannot be silently ignored; structured propagation
Manual string + strlen	std::string / std::string_view	No buffer overflows, RAII lifetime
qsort with void*	std::sort with lambda	Inlineable, type-safe, 2-3× faster

Topics

What you already know (it's most of it)

C++ is a superset of most C. Your struct layouts, pointer arithmetic, bit manipulation, and platform-specific tricks all work as-is.

The C++ type system additions

References, bool, nullptr, enum class, constexpr — strict upgrades over C equivalents. No behavior change, just safety.

Classes are structs with methods

A C++ class is literally a struct. Add member functions, constructors, and destructors. The struct layout is identical.

RAII: the destructor does your cleanup

Replace every free(), close(), unlock() with a destructor. Stack-based objects clean up automatically even on error paths.

Templates replace most macros

Function-like macros → inline functions or function templates. Type-parameterized macros → class/function templates.

std::vector replaces C arrays + size

vector<int> is a C array under the hood (contiguous memory, data() returns a pointer). But with bounds checking and automatic resize.

Namespaces replace prefixes

gl_DrawArrays, SDL_Init, FMOD_... → DrawArrays (inside namespace gl), Init (namespace SDL). Cleaner, same binary output.

Coming soon

Linking C and C++ (extern "C")

Calling C from C++ and vice versa. Name mangling, extern "C", and the correct way to write headers used from both.

The C++ standard library vs libc

When to use std::sort vs qsort, std::string vs char*, std::fstream vs FILE*. The C standard library still works — C++ just has better options.

Coming soon

C++ in embedded / freestanding

No RTTI, no exceptions, no stdlib allocation — C++ still gives you templates, constexpr, RAII, and concepts. C++ embedded is not scary C++.