diff --git a/README.md b/README.md index 3a41294..e9818bb 100644 --- a/README.md +++ b/README.md @@ -184,7 +184,9 @@ 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`. -- 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. +- 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. + - Find every .log file and execute a tail -f on all of them simultaneously. `find . -type f -name "*.log" | awk '{print}' ORS=' ' | sed 's/^/tail -f /' | sh` - To replace all occurrences of a string in place, in one or more files: ```sh