whatis:tldr:1ad65

The command "whatis --regex '${wish[0-9]-[0-9]}'" is used to search for manual pages (also known as man pages) that match a specific regular expression pattern.

Let's break down the command into its components:

1. "whatis": This is a command used to search for descriptions of command-line programs and system calls in the manual pages.

2. "--regex": This flag is used to indicate that the search pattern provided is a regular expression.

3. '${wish[0-9]-[0-9]}': This is the regular expression pattern to search for. Here's what it means:

   • '${wish[0-9]': This part is checking for a pattern with "wish" followed by a single digit (0-9).

   • '-': This is checking for a hyphen (-) character.

   • '[0-9]}': This part is checking for another single digit (0-9) after the hyphen.

   So, the overall regular expression pattern is searching for instances of "wish" followed by two digits separated by a hyphen.

When executing the command, the system will look for any man pages that match this pattern, and it will provide a brief description of each matching page.