Editing Text file (section)

=== Unix text files ===

On [[Unix-like]] operating systems, text files format is precisely described: [[POSIX]] defines a text file as a file that contains characters organized into zero or more lines,<ref>{{cite web |url=http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_403 |title=3.403 Text File |work=[[POSIX|IEEE Std 1003.1, 2017 Edition]] |publisher=[[IEEE Computer Society]] |access-date=2019-03-01}}</ref> where lines are sequences of zero or more non-newline characters plus a terminating newline character,<ref>{{cite web |url=http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_206 |title=3.206 Line |work=[[POSIX|IEEE Std 1003.1, 2013 Edition]] |publisher=[[IEEE Computer Society]] |access-date=2015-12-15}}</ref> normally LF.

Additionally, POSIX defines a '''{{vanchor|printable file}}''' as a text file whose characters are printable or space or backspace according to regional rules. This excludes most control characters, which are not printable.<ref>{{cite web |url=http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_284 |title=3.284 Printable File |work=[[POSIX|IEEE Std 1003.1, 2013 Edition]] |publisher=[[IEEE Computer Society]] |access-date=2015-12-15}}</ref>