Bash has no native floating point support. The (( )) and $(( )) arithmetic expansions only handle integers. For decimals, you need external tools — primarily bc, awk, or dc. bc: Arbitrary Precision Calculator bc is the standard choice for floating point math in shell scripts. It’s POSIX-compliant, available on every Unix-like system, and handles…
The GNU C Reference Manual is the authoritative resource for C as implemented by GCC. It’s a pure reference—not a tutorial—covering every linguistic construct, GCC-specific extensions, and implementation details you’ll encounter when compiling C code. What the Manual Covers The GNU C Reference Manual documents: All C language keywords and their behavior Operator precedence and…
GCC allows you to embed assembly code directly in C/C++ programs through inline assembly (asm and __asm__). This is useful when you need fine-grained control over processor execution—forcing variables into specific registers, reading CPU state efficiently, or hand-optimizing critical sections verified by profiling. Basic Syntax GCC uses AT&T syntax by default on x86/x86-64. The simplest…
x86-64 (Intel 64, AMD64) is the dominant 64-bit instruction set architecture for consumer and enterprise computing. Whether you’re reverse-engineering binaries, writing performance-critical code, or understanding system internals, a solid grasp of x86-64 assembly is essential. Learning Foundations CMU’s Introduction to Computer Systems (15-213) course materials remain the gold standard for foundational machine-level programming. The accompanying…
The C language itself provides no built-in mechanisms for input/output, memory management, string manipulation, or process control. These essential capabilities come from the C standard library — a collection of functions, macros, and data types that you link with your programs at compile time. The GNU C Library (glibc) is the standard C library used…
GDB is the standard debugger for C/C++ development on Linux. This reference covers essential commands for breakpoints, execution control, inspection, and troubleshooting common debugging scenarios. Starting GDB gdb ./program gdb ./program core.dump # Debug with core file gdb -p <pid> # Attach to running process gdb –args ./program arg1 arg2 # Pass arguments to program…
fclose() closes a file stream and disassociates it from its underlying file descriptor. It’s part of the C standard library, defined in <stdio.h>. #include <stdio.h> int fclose(FILE *stream); When called, fclose() flushes buffered output, closes the file descriptor, and deallocates the FILE structure. The function works with both input and output streams. After fclose() returns,…
Vim’s indentation system provides multiple approaches for formatting C/C++ code, from built-in operators to external formatters. The native tools work reliably for most tasks, while external formatters enforce stricter style rules when needed. The Indentation Operator and Text Objects The = operator re-indents text. It requires a motion or text object to specify what to…
C allows flexibility in coding style, but discipline matters. Consistent structure makes code readable, maintainable, and less prone to bugs. Here’s a practical approach that scales from small utilities to large projects. One Header Per Source File Pair each source file (.c) with a corresponding header file (.h). The header serves as the module’s public…
cgdb is a curses-based frontend to gdb that keeps your source code visible while you debug. Unlike raw gdb, it splits the interface into two panes: source code on top, gdb command prompt below. If you’re already comfortable with Vim keybindings, cgdb feels natural—it uses the same navigation keys and modal editing paradigms you’re used…
Use std::filesystem for all new code. It’s exception-safe, cross-platform, and requires no external dependencies. #include <filesystem> #include <iostream> void ListAllFiles(const char *folderPath) { for (const auto& entry : std::filesystem::recursive_directory_iterator(folderPath)) { std::cout << entry.path() << std::endl; } } To filter by file type, check the entry status: void ListRegularFiles(const char *folderPath) { for (const auto& entry…
Serial communication remains essential for embedded systems, microcontroller programming, and legacy hardware integration. The Win32 API provides direct control over COM ports through a straightforward set of functions: CreateFile() to open the port, GetCommState() and SetCommState() to configure parameters, and ReadFile()/WriteFile() for I/O operations. Opening the COM Port Start by opening the port with appropriate…
When debugging and optimizing C/C++ programs, you need to see how the compiler translates your source code into assembly. A mixed source and assembly listing lets you trace exactly what machine instructions correspond to each line of your source. Using objdump (Recommended Modern Approach) The most straightforward method is to compile with debugging symbols and…
In MFC applications, pressing ESC or Enter closes a dialog by default. To prevent this, override CDialog::PreTranslateMessage() and intercept these key events before they reach the default handler. Basic Implementation BOOL CResultCollectorDlg::PreTranslateMessage(MSG* pMsg) { if(pMsg->message == WM_KEYDOWN) { switch(pMsg->wParam) { case VK_RETURN: // Enter key return TRUE; case VK_ESCAPE: // ESC key return TRUE; }…
Managing proxy settings through the GUI is tedious, especially when you need to switch between multiple proxy servers frequently. Rather than hunting through settings menus each time, command-line tools eliminate friction and enable scripted deployments across your infrastructure. The original SetProxy tool is outdated and incompatible with modern Windows versions. Use netsh or PowerShell instead—both…
Java Applets were obsolete by 2016 and removed from Java 9+. If you need a browser-based system monitoring dashboard, use WebSockets or Server-Sent Events paired with modern JavaScript charting libraries. WebSocket + Python Backend Architecture The most practical setup streams metrics from a Python backend to connected clients using WebSockets. Clients render real-time charts without…
Building tabular data displays in MFC requires significant effort since the framework lacks a native grid control. Developers historically filled this gap with third-party solutions, but the landscape has shifted considerably. GridCtrl: The Legacy Choice The GridCtrl implementation from CodeProject was the de facto standard for years. If you’re maintaining MFC applications in 2026, you’ll…
OCaml is a practical functional language with strong static typing and pattern matching. If you’re coming from systems programming or looking to add functional paradigms to your toolkit, these resources will accelerate your learning. Primary Learning Resources Real World OCaml by Yaron Minsky, Anil Madhavapeddy, and Jason Hickey remains the standard reference for modern OCaml…
Embedding child dialogs within a parent dialog is a practical technique for organizing complex MFC applications. This approach modularizes your UI by breaking it into logical, reusable components rather than cramming everything into a single dialog resource. Basic Implementation Create the child dialog as a WS_CHILD window and position it within the parent’s client area….
Blocking window closure in MFC applications is necessary for critical operations, multi-step dialogs, and workflows that require user confirmation before exit. This requires handling both the close button and the Alt+F4 keyboard shortcut. Removing the Close Button from the System Menu The simplest approach is to remove SC_CLOSE from the system menu in your dialog’s…