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@@ -206,6 +206,8 @@ 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: