c-pro_skill

Overview

This skill helps you write efficient, safe C code for systems and performance-critical projects. It focuses on correct memory management, pointer arithmetic, POSIX system calls, and practices for embedded and kernel-level development. The skill provides code patterns, Makefiles, tests, and guidance to produce leak-free, profiled, and portable C99/C11 code.

How this skill works

I inspect code for ownership, allocation patterns, and unchecked return values, and suggest fixes that ensure every malloc has a matching free. I provide idiomatic examples for pointer use, memory pools, pthread synchronization, and validated system-call wrappers. I also produce Makefiles with strict compiler flags and example unit tests, plus instructions for using valgrind, gdb, and profiling tools before optimizing.

When to use it

• Building embedded firmware with tight RAM/stack constraints
• Writing kernel modules or low-level POSIX-compliant services
• Optimizing hot paths in performance-critical code
• Auditing code for memory leaks, race conditions, or undefined behavior
• Preparing code for production with unit tests and CI-friendly builds

Best practices

• Always check return values for malloc, fopen, read, write, and system calls
• Define clear ownership rules in comments and function signatures
• Prefer stack for small objects; use pools or arenas to manage many allocations
• Enable -Wall -Wextra and treat warnings as errors during CI
• Profile before changing algorithms; measure with perf or gprof

Example use cases

• Convert ad-hoc malloc/free usage into a memory-pool API with clear ownership
• Wrap system calls with retry and errno-aware error handling for robustness
• Refactor a multithreaded component to use pthread mutexes and condition variables safely
• Provide a Makefile and unit test scaffold for an embedded sensor driver
• Diagnose and fix heap leaks using valgrind reports and fix-point tests