Programming

GSoC 2025 Final Report: Implementing POSIX Issue 8 Functions in RTEMS Project Summary My Google Summer of Code 2025 project focused on enhancing RTEMS’ POSIX compliance by implementing critical functions introduced in POSIX Issue 8. RTEMS (Real-Time Executive for Multiprocessor Systems) is a real-time operating system designed for embedded and mission-critical applications, including space exploration and aerospace systems. The goal of this project was to analyze, implement, and thoroughly test missing POSIX Issue 8 APIs to bring RTEMS closer to full POSIX compliance, enabling better portability and functionality for real-time applications. ...

Time APIs in C: From time() to timespec_get() Time measurement in computing has evolved from simple second-based timestamps to high-precision APIs. This guide covers the main time functions available in C, focusing on timespec_get() - a C11 standard function and its implementation in real-time systems. Why Multiple Time APIs? Time measurement serves different purposes: file timestamps, process scheduling, timeouts, performance measurement, and real-time applications. Each use case has different precision and reliability requirements, leading to multiple APIs optimized for specific needs. ...

The Exit Family: Understanding Program Termination in C When a C program needs to terminate, there are several different functions available, each with distinct behaviors and use cases. Understanding the differences between exit(), _exit(), _Exit(), abort(), and quick_exit() is crucial for writing robust system software and understanding how programs interact with the operating system. The Standard exit() Function The exit() function is the most commonly used program termination function, defined in <stdlib.h>. It performs a clean shutdown of the program by executing cleanup routines before terminating. ...

GSoC 2025 Midterm Evaluation: Implementing POSIX Issue 8 Functions in RTEMS As I reach the midpoint of my Google Summer of Code 2025 journey with RTEMS, I’m excited to share the progress I’ve made on implementing POSIX Issue 8 functions. This project aims to enhance RTEMS’ POSIX compliance by adding support for new functions introduced in the latest POSIX standard. Project Overview My GSoC project focuses on implementing and testing 8 key POSIX Issue 8 functions in RTEMS: ...

Contributing to Newlib: A Step-by-Step Guide If you’re interested in contributing to Newlib, the C standard library used by many embedded systems (including RTEMS and Cygwin), this guide will walk you through the process of submitting patches. What is Newlib? Newlib is a C standard library implementation intended for use on embedded systems. It’s widely used in projects like RTEMS, Cygwin, and various bare-metal environments. Part 1: Creating and Submitting Patches 1. Clone the Repository First, you need to clone the newlib-cygwin repository: ...