| #include <SPI.h> | |
| #include <Wire.h> | |
| #include <Adafruit_GFX.h> | |
| #include <Adafruit_SSD1306.h> | |
| #define OLED_DC 6 | |
| #define OLED_CS 7 | |
| #define OLED_RESET 8 | |
| #define PIN_ENCODER_A 4 //Micro pin 4 - encoder A | |
| #define PIN_ENCODER_B 6 |
| /*************************************************** | |
| This is a library for our optical Fingerprint sensor | |
| Designed specifically to work with the Adafruit BMP085 Breakout | |
| ----> http://www.adafruit.com/products/751 | |
| These displays use TTL Serial to communicate, 2 pins are required to | |
| interface | |
| Adafruit invests time and resources providing this open source code, | |
| please support Adafruit and open-source hardware by purchasing |
| /**************************************************************************/ | |
| /*! | |
| @file readntag203.pde | |
| @author KTOWN (Adafruit Industries) | |
| @license BSD (see license.txt) | |
| This example will wait for any NTAG203 or NTAG213 card or tag, | |
| and will attempt to read from it. | |
| This is an example sketch for the Adafruit PN532 NFC/RFID breakout boards |
| @Test | |
| public void testOptional() { | |
| assertEquals(Optional.of( | |
| new AClass()) | |
| .map(AClass::getSomeObject) | |
| .map(BClass::getSomeText) | |
| .map(String::trim) | |
| .orElse(""), ""); | |
| assertEquals(Optional.of( | |
| new AClass(new BClass())) |
It is possible to redirect some input to TTY device by standard IO redirection.
echo ahoj > /dev/tty1
Such redirection will however end in the output buffer of the TTY device so the characters will be ghosts - visible on the terminal, but not effective. It is, in fact, not possible by standard tools to redirect input to terminal as if it is a real input from keyboard.
| mkfifo reply | |
| ncat -kl 8765 < reply | ncat 127.0.0.1 4567 > reply # listens on port 8765 and redirects to localhost:4567. Runs until C-c. | |
| rm reply # cleanup after end |
Standard grep has one weakness regarding the log files - it doesn't handle multiline log entries well. For example logs of Java
programs are famous to have many lines of stack traces in a single log item. It is possible to use -A grep parameter but this
adds lines also for log items that doesn't have any other lines in them resulting in showing log entries which doesn't contain the
search term which is very confusing.
I was so frustrated greping through a log file once that I tried a more exotic approach using Lex and it turned out it's extremely easy with it. I realized that it's in fact raison d’être of lex and that it's very dumb not to use it in the first place.
| <?xml version="1.0" encoding="UTF-8"?> | |
| <result> | |
| <status>success</status> | |
| <html xmlns="http://www.w3.org/1999/xhtml"> | |
| <a id="email">somebody@example.com</a> | |
| <span id="filename">file.ext</span> | |
| <table> | |
| <thead> | |
| <tr> | |
| <th>Dodavatel</th> |
Landauer's principle: There is a minimum energy needed to delete information because of the laws of thermodynamics.
Limits of Koomey's law: Because of Landauer's principle, for non-reversible computation there is a limit on number of computations per joule.
Margolus–Levitin theorem: Even reversible computing is constrained in number of computations per joule.
Bekenstein bound: Entropy in given finite space is limited.
Bremermann's limit: Implication of Bekenstein bound is that there is a limit on computational power of a computer.