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MAC TEXT FILE CR LF DRIVERS
MAC TEXT FILE CR LF MANUAL

That is why the sequence was always sent with the CR first. The separation of the two functions concealed the fact that the print head could not return from the far right to the beginning of the next line in one-character time.

MAC TEXT FILE CR LF DRIVERS

On these systems, text was often routinely composed to be compatible with these printers, since the concept of device drivers hiding such hardware details from the application was not yet well developed applications had to talk directly to the teletype machine and follow its conventions. The sequence CR+LF was in common use on many early computer systems that had adopted teletype machines, typically an ASR33, as a console device, because this sequence was required to position those printers at the start of a new line. If you're curious, as I was, about the historical basis for these decisions, Wikipedia delivers all the newline trivia you could possibly want, and more: Pretty much business as usual in computing.

Completely arbitrary platform "standards" for what is exactly the same function.

Confusing terms based on archaic hardware that is no longer in use, and is confounding to new users who have no point of reference for said terms.

On printers, teletypes, and computer terminals that were not capable of displaying graphics, the carriage return was used without moving to the next line to allow characters to be placed on top of existing characters to produce character graphics, underlines, and crossed out text. The distinction between CR and LF does seem kind of pointless - why would you want to move to the beginning of a line without also advancing to the next line? This is another analog artifact, as Wikipedia explains: In all honesty, I'm not quite old enough to have used electric typewriters, so I have a dim recollection, at best, of the entire process. On a typewriter, pressing Line Feed causes the carriage roller to push up one line - without changing the position of the carriage itself - while the Carriage Return lever slides the carriage back to the beginning of the line.

MAC TEXT FILE CR LF MANUAL

The Carriage Return (CR) and Line Feed (LF) terms derive from manual typewriters, and old printers based on typewriter-like mechanisms (typically referred to as "Daisywheel" printers).

But newlines aren't a universally accepted standard they are different depending who you ask, and what platform they happen to be computing on: The invisible problem characters in this case are newlines.ĭid you ever wonder what was at the end of your lines? As a programmer, I knew there were end of line characters, but I honestly never thought much about them. The answer to this puzzle lies in our old friend, invisible characters that we can't see but that are totally not out to get us. Opening the file in a different, smarter text editor results in the file displayed properly in multiple paragraphs. Have you ever opened a simple little ASCII text file to see it inexplicably displayed as onegiantunbrokenline?