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Linux - Operating System

Paging, Concurrency, Time

Paging A page of memory is the smallest fixed-length block of virtual memory managed by OS. To use virtual memory, the OS needs to transfer pages between the main memory and the secondary memory. ...

Posted by Rico's Nerd Cluster on January 20, 2018

Linux Miscellaneous Thingies

Window Focus, Screenshots, File System, Shortkeys, UART, Tmux, ffmpeg, Firefox, Chrome, Power Modes

=============================================================================================================== Screenshots =======================================================================...

Posted by Rico's Nerd Cluster on January 17, 2018

Linux - Packaging Systems

apt, dpkg

Installation Chain apt, apt-get, apt-cache talks to the repository servers, download .deb, calculate dependency tree, the hand the final files to dpkg for the actual install. E.g., 1 sudo apt ins...

Posted by Rico's Nerd Cluster on January 16, 2018

Linux - Programming And Toolchain

ldd

ELF and Dynamic Linking Executable and Linkable Format (ELF) is the standard binary file format on Linux, most BSDs, and many embedded systems. It replaces older a.out and COFF formats. | Aspect ...

Posted by Rico's Nerd Cluster on January 13, 2018

Linux - Filesystem

inode, soft/symbolic link, FIFO

Inode On every Unix-style filesystem (ext4, XFS, APFS, etc.), each regular file, directory, FIFO, … is represented on disk by a tiny metadata record called an inode (“index node”). That’s like a f...

Posted by Rico's Nerd Cluster on January 10, 2018

Linux - Udev Rules, Systemd Services, inotify

Udev Rules Systemd Services, Inotify

Udev Unix Kernel is a monolithic kernel and provides API to access these hardware. Udev is a device manager of Linux Kernel, and serves as a successor of the Unix Kernel. It handles device nodes i...

Posted by Rico's Nerd Cluster on January 7, 2018

Linux - SSH and X Window System

X Window System, SSH, Static IP

SSH Generate an SSH Key: ssh-keygen -t rsa -b 4096. This will create ~/.ssh/id_rsa and optionally sets a passphrase Copy ssh onto a remote machine: ssh-copy-id username@rem...

Posted by Rico's Nerd Cluster on January 5, 2018

Electronics - General Science Facts

Adiabatic Cooling, Centripedal & Centrifugal Forces

Adiabatic Cooling In an adiabatic process, the system does not gain or lose heat (Q=0Q=0), meaning that all changes in internal energy come from work done by or on the gas. For an ideal gas, the i...

Posted by Rico's Nerd Cluster on July 1, 2017

Literature - The Wealthy Barber Notes

Financial Literacy

Roy’s Story “We all felt bad about Roy having to put off his dream of becoming a lawyer, but deep down we knew that he was doing the right thing. You got to be there when your family needs you,...

Posted by Rico's Nerd Cluster on June 5, 2017

Electronics - General Electronics Notes

Encoders, Motors, Capacitors, IMU, Testing, Telecommunication

Electronics EEPROM EEPROM (Electrically Erasable Programmable Read-Only Memory) is a type of non-volatile memory used in microcontrollers to store small amounts of data that must be preserved whe...

Posted by Rico's Nerd Cluster on June 3, 2017

Rico's Nerd Cluster