grep searches for regexp by default on Linux, and the '-F' switch is required for the exact string.
Corrected by replacing search_string with search_pattern, or adding the mentioned switch.
By default, grep already uses regular expressions when searching.
The example `grep -e {{^regex$}} {{path/to/file}}` is the same as `grep {{^regex$}} {{path/to/file}}`.
However, because of the comment about extended regular expressions, I mistakenly assumed `-e` was the option to enable it.
I believe most people would refer to `tldr` in this use case looking for the `-E` extended regular expressions.
With this in mind, I believe that example would be better rephrased as this pull request makes it.
- use "case-insensitive" in the description of the -i option to make the initialism clear
- use path/to/file instead of file_path
- mention extended regex syntax and expand first occurrence to spell "regular expression"
- clarify wording of the -C example description