Note: This post covers Linux fundamentals. Core concepts remain valid, but some commands and package names may differ on modern distributions. See your distro’s documentation for current details. Make is a utility that automatically builds executable programs and libraries from source code by reading files called makefiles which specify how to derive the target program….
Note: This post covers C/C++ programming and debugging fundamentals. Core concepts remain valid. For current references, see cppreference.com and GDB documentation. One cool feature of gcc is that it can inline assembly into C code. With inline assembly, the programmer can precisely control the execution of the processor, such as forcing variables to use registers,…
“The C language provides no built-in facilities for performing such common operations as input/output, memory management, string manipulation, and the like. Instead, these facilities are defined in a standard library, which you compile and link with your programs. The GNU C library, described in this document, defines all of the library functions that are specified…
Learning Linux: A Curated Path for Beginners Starting with Linux can feel intimidating. The terminology, the command line, the endless configuration options—it’s a lot. But that initial confusion fades quickly. Once you get comfortable with the fundamentals, Linux becomes intuitive, and you’ll wonder why you didn’t start sooner. This guide points you toward solid tutorials…
Installing ns-2 and ns-3 on Fedora Linux ns (Network Simulator) is a discrete-event simulator used primarily for research and educational purposes in networking. The two major versions—ns-2 and ns-3—are substantially different in architecture and usage patterns. This guide covers installation on current Fedora systems. Installing ns-2 on Fedora Note: ns-2 is legacy software and requires…
pgrep and pkill: Process Management Commands pgrep and pkill are essential tools for finding and signaling processes by name and attributes. They’re far more precise than grepping ps output and should be your go-to for process management scripts and one-liners. pgrep: Find Process IDs pgrep searches running processes and outputs matching PIDs. All selection criteria…
Setting Date, Time, and Timezone in Linux Understanding and managing system time is crucial for logging, cron jobs, SSL certificates, and system synchronization. Here’s how to handle it properly on modern Linux systems. Unix Time (POSIX Time) Unix time represents seconds elapsed since 00:00:00 UTC on January 1, 1970, excluding leap seconds. Get the current…
Linux Port Forwarding Using iptables Port forwarding allows external hosts to reach services inside a private network by mapping traffic from a public address to an internal one. On Linux, this is implemented through iptables rules that modify packet headers as they traverse the kernel’s netfilter framework. Common use cases include exposing HTTP/HTTPS servers from…
Setting Up a SOCKS Proxy Over SSH A SOCKS5 proxy tunneled through SSH provides encrypted communication between your client and a remote server. This is useful for bypassing network restrictions, securing connections on untrusted networks, or routing traffic through a trusted server. Basic Setup The simplest approach uses SSH’s dynamic port forwarding with the -D…
Removing ^M Carriage Returns in Vim When you open a Windows file in Vim (or Neovim), you’ll often see ^M characters at the end of lines. These are carriage returns (\r) from Windows line endings (CRLF), which don’t display properly on Unix-like systems that expect LF-only line endings. Quick Fix The fastest way to remove…
NVIDIA Driver Installation on Fedora Installing NVIDIA drivers on Fedora is straightforward when using RPM Fusion repositories. This guide covers modern Fedora releases (39+) using DNF package management. Prerequisites Before starting, determine which driver your GPU requires. Check the NVIDIA driver download page or use this command to identify your GPU: lspci | grep -i…
Mount an ISO image Mounting an ISO on Linux requires a loop device. Modern systems support this directly with mount: sudo mount -o loop /path/to/image.iso /mnt/mount-point Or use the -t iso9660 option for explicit filesystem specification: sudo mount -t iso9660 -o loop /path/to/image.iso /mnt/mount-point To unmount: sudo umount /mnt/mount-point For temporary mounts that don’t require…
Crontab Basics Crontab controls what runs and when. Each crontab entry has this format: .—————- minute (0-59) | .————- hour (0-23) | | .———- day of month (1-31) | | | .——- month (1-12) OR jan,feb,mar,apr … | | | | .—- day of week (0-6) (Sunday=0 or 7) OR sun,mon,tue … | | |…