Look up errno names and descriptions
errno {name-or-code} errno [-ls] [--list] errno [-s] [--search] {word} errno [-S] [--search-all-locales] {word}
errno looks up errno macro names, errno codes, and the corresponding descriptions. For example, if given ENOENT on a Linux system, it prints out the code 2 and the description "No such file or directory". If given the code 2, it printes ENOENT and the same description.
-l, --list
List all errno values.
-s, --search
Search for errors whose description contains all the given words (case-insensitive).
-S, --search-all-locales
Like --search, but searches all installed locales.
Lars Wirzenius