From 2c5df2316990966064edf3e79514b9f2cb83dc25 Mon Sep 17 00:00:00 2001 From: Diomidis Spinellis Date: Tue, 26 Jan 2016 20:57:29 +0200 Subject: [PATCH] Add command-specific environment settings --- README.md | 2 ++ 1 file changed, 2 insertions(+) diff --git a/README.md b/README.md index ef25da8..f530536 100644 --- a/README.md +++ b/README.md @@ -204,6 +204,8 @@ Notes: - Know that locale affects a lot of command line tools in subtle ways, including sorting order (collation) and performance. Most Linux installations will set `LANG` or other locale variables to a local setting like US English. But be aware sorting will change if you change locale. And know i18n routines can make sort or other commands run *many times* slower. In some situations (such as the set operations or uniqueness operations below) you can safely ignore slow i18n routines entirely and use traditional byte-based sort order, using `export LC_ALL=C`. +- You can set a specific command's environment by prefixing its invocation with the environment variable settings, as in `TZ=Pacific/Fiji date`. + - Know basic `awk` and `sed` for simple data munging. For example, summing all numbers in the third column of a text file: `awk '{ x += $3 } END { print x }'`. This is probably 3X faster and 3X shorter than equivalent Python. - To replace all occurrences of a string in place, in one or more files: