From a44c628ad2132ac0de89f15e8070cfb753e6444d Mon Sep 17 00:00:00 2001 From: Joshua Levy Date: Wed, 17 Jun 2015 20:20:18 -0700 Subject: [PATCH] Add note about sort -u. Addresses #27 and #63 while preserving clarity. --- README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/README.md b/README.md index 8c61a4b..0864b97 100644 --- a/README.md +++ b/README.md @@ -235,7 +235,7 @@ Scope: A few examples of piecing together commands: -- It is remarkably helpful sometimes that you can do set intersection, union, and difference of text files via `sort`/`uniq`. Suppose `a` and `b` are text files that are already uniqued. This is fast, and works on files of arbitrary size, up to many gigabytes. (Sort is not limited by memory, though you may need to use the `-T` option if `/tmp` is on a small root partition.) See also the note about `LC_ALL` above. +- It is remarkably helpful sometimes that you can do set intersection, union, and difference of text files via `sort`/`uniq`. Suppose `a` and `b` are text files that are already uniqued. This is fast, and works on files of arbitrary size, up to many gigabytes. (Sort is not limited by memory, though you may need to use the `-T` option if `/tmp` is on a small root partition.) See also the note about `LC_ALL` above and `sort`'s `-u` option (left out for clarity below). ```sh cat a b | sort | uniq > c # c is a union b cat a b | sort | uniq -d > c # c is a intersect b