I believe the article was originally written by fede.tft.
It appears they have copied source code to github and updated it for C++11: https://github.com/fedetft/serial-port
The serial port protocol is one of the most long lived protocols currently in use. According to wikipedia, it has been standadized in 1969. First, a note: here we're talking about the RS232 serial protocol. This note is necessary because there are many other serial protocols, like SPI, I2C, CAN, and even USB and SATA.
Some time ago, when the Internet connections were done using a 56k modem, the serial port was the most common way of connecting a modem to a computer. Now that we have ADSL modems, the serial ports have disappeared from newer computers, but the protocol is still widely used.
In fact, most microcontrollers, even the newer ones have one or more peripherals capable of communicating using this protocol, and from the PC side, all operating system