Language Selection

English French German Italian Portuguese Spanish

the futility of termcap in Linux

Filed under
Linux

Let's stop a moment and examine the futility of termcap in Linux.
Back in the 1970's Unix systems used to output to various hardware devices. First there were teletypes (most often the ASR-33, because they could be bought cheaply secondhand and refurbished by hobbyists). Teletypes were printers with keyboards attached, hooked up to a serial cable. Everything sent to the serial cable was printed with ink on paper, and the keys pressed by the user were sent the other way along the serial cable for the computer too read.

Note: we're not even talking dot-matrix printers here, the ink ribbon was generally struck by a daisy wheel or similar, so there was no possibility of bitmapped graphics. The characters were struck by good old metal type, dating back to Gutenberg.

This is what "tty" is an abbreviation for: teletype. The Unix console infrastructure still thinks in terms of serial ports connected to printers with keyboards attached. Newline and linefeed being separate characters, waiting until a full line of text is typed before processing it, inability to programmatically read back what was written. Even the ctrl-G "bell" character rang an actual metal BELL. These machines not only needed their ink ribons replaced, they needed to be periodically cleaned, oiled, and various pieces tightened and straightened because they rattled apart. It was almost steampunk.

Then in the 1970's "glass tty" devices were introduced, which connected the serial cable to a box with a CRT and keyboard, instead of printer and keyboard. This new style of terminal was a drop-in replacement for teletypes.

rest here




More in Tux Machines

Today in Techrights

Gorgeous Live Voyager 16.04 Linux OS Comes Hot on the Heels of Ubuntu 16.04 LTS

The team of developers behind the Live Voyager desktop-oriented operating system have announced today, May 1, 2016, the release and immediate availability for download of Voyager 16.04 LTS. Read more

BlackArch Linux Now Provides over 1,400 Penetration Testing Tools, New ISO Lands

The BlackArch Linux devs have been preparing this for months, but now it is finally here, the new ISO image of the Arch Linux-based operating system designed for hackers and security professionals. Read more

If I needed to leave Android, I'd use Sailfish OS

Sailfish OS may be unknown to most people, but if Android was to disappear tomorrow, this would be the direction I'd head. Sailfish OS is an open source mobile operating system that offers speed and simplicity like no other. And, in my opinion, is the best alternative to Android. Read more