- Hex fiend line delimiter drivers#
- Hex fiend line delimiter driver#
- Hex fiend line delimiter code#
- Hex fiend line delimiter iso#
Unix followed the Multics practice, and later Unix-like systems followed Unix. Perhaps more importantly, the use of LF alone as a line terminator had already been incorporated into drafts of the eventual ISO/IEC 646 standard. What seems like a more obvious choice- CR-was not used, as CR provided the useful function of overprinting one line with another to create boldface, underscore and strikethrough effects.
Hex fiend line delimiter driver#
Multics used a device driver to translate this character to whatever sequence a printer needed (including extra padding characters), and the single byte was more convenient for programming. The Multics operating system began development in 1964 and used LF alone as its newline. From there MS-DOS (1981) adopted CP/M's CR+ LF in order to be compatible, and this convention was inherited by Microsoft's later Windows operating system.
CP/M also used it in order to print on the same terminals that minicomputers used. Most minicomputer systems from DEC used this convention. Therefore, text was routinely composed to satisfy the needs of Teletype machines.
Hex fiend line delimiter drivers#
On such systems, applications had to talk directly to the Teletype machine and follow its conventions since the concept of device drivers hiding such hardware details from the application was not yet well developed. Many early video displays also required multiple character times to scroll the display.
"The solution was to make the newline two characters: CR to move the carriage to column one, and LF to move the paper up." In fact, it was often necessary to send extra characters-extraneous CRs or NULs-which are ignored but give the print head time to move to the left margin. Any character printed after a CR would often print as a smudge in the middle of the page while the print head was still moving the carriage back to the first position. The separation of newline into two functions concealed the fact that the print head could not return from the far right to the beginning of the next line in time to print the next character. The sequence CR+ LF was commonly used on many early computer systems that had adopted Teletype machines-typically a Teletype Model 33 ASR-as a console device, because this sequence was required to position those printers at the start of a new line.
Hex fiend line delimiter iso#
During the period of 1963 to 1968, the ISO draft standards supported the use of either CR+ LF or LF alone as a newline, while the ASA drafts supported only CR+ LF. ASCII was developed simultaneously by the International Organization for Standardization (ISO) and the American Standards Association (ASA), the latter being the predecessor organization to American National Standards Institute (ANSI). Later, in the age of modern teleprinters, standardized character set control codes were developed to aid in white space text formatting.
Hex fiend line delimiter code#
In particular the Morse prosign BT (mnemonic break text) represented by the concatenation of literal textual Morse codes "B" and "T" characters sent without the normal inter-character spacing is used in Morse code to encode and indicate a new line or new section in a formal text message. In the mid-1800s, long before the advent of teleprinters and teletype machines, Morse code operators or telegraphists invented and used Morse code prosigns to encode white space text formatting in formal written text messages. This character, or a sequence of characters, is used to signify the end of a line of text and the start of a new one. Newline (frequently called line ending, end of line ( EOL), next line ( NEL) or line break) is a control character or sequence of control characters in character encoding specifications such as ASCII, EBCDIC, Unicode, etc. Newline inserted between the words "Hello" and "world"
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