Date: Tue, 24 Dec 2019 00:47:40 -0500
From: Eli Schwartz <[email protected]>
Message-ID: <[email protected]>
| What is "recent" about sort -u? I can find it listed as a mandatory
| option in the POSIX 2004 manual.
The -u option appaeared in 7th edition Bell Labs Unix (1979) [I would
assume it was actually implemented somewhat earlier, that's when 7th
edition was released to the rest of the world.]
Also note that sort -u and sort | uniq are not quite the same, the -u
option only considers the key fields when deciding which records (lines)
are unique (of course, with no key options, the whole line is the key,
in which case they are more or less the same).
kre