Add Grep For Multiple Patterns as a unix til

Author: jbranchaud

README.md

@@ -269,6 +269,7 @@ _305 TILs and counting..._
 - [Find Newer Files](unix/find-newer-files.md)
 - [Global Substitution On The Previous Command](unix/global-substitution-on-the-previous-command.md)
 - [Grep For Files Without A Match](unix/grep-for-files-without-a-match.md)
+- [Grep For Multiple Patterns](unix/grep-for-multiple-patterns.md)
 - [Hexdump A Compiled File](unix/hexdump-a-compiled-file.md)
 - [Kill Everything Running On A Certain Port](unix/kill-everything-running-on-a-certain-port.md)
 - [Killing A Frozen SSH Session](unix/killing-a-frozen-ssh-session.md)

unix/grep-for-multiple-patterns.md

@@ -0,0 +1,12 @@
+# Grep For Multiple Patterns
+
+You can use the `-e` flag with the `grep` command to search for a pattern.
+Additionally, you can use multiple `-e` flags to search for multiple
+patterns. For instance, if you want to search for occurrences of `ruby` and
+`clojure` in a `README.md` file, use the following command:
+
+```
+$ grep -e ruby -e clojure README.md
+```
+
+See `man grep` for more details.