What is the meaning of abbreviation ynaq in nethack?

I am new to Nethack, English is not my first language, and the first game screen shows:

NetHack, Copyright 1985-2018
         By Stichting Mathematisch Centrum and M. Stephenson.
         Version 3.6.1 Unix, revised Sep 16 16:35:42 2018.
         See license for details.


Shall I pick a character's race, role, gender and alignment for you? [ynaq]

Looking at each letter in the option list, I presume that they mean:

y: yes
n: no
a: unknown
q: quit or exit

What does the "a" option do?

nethack

Best Answer

It's hard to find information on this, and I've often wondered it myself, but it seems to stand for "all". Even the Nethack Wiki doesn't define "ynaq".

In the case of item accumulation:

Typing y picks up that item, and displays the next.
Typing n displays the next item.
Typing a picks up that item, and all remaining items of the named types. The program will not allow the player to pick up any item which is too heavy.
Typing q aborts the command.

In the case of starting a new game, it would make all relevant choices for you so the game can begin in earnest.

Do note that when pressing q your character will be deleted. It's best to save instead using Shift+S.

References:

https://thekill08.wordpress.com/2008/03/15/hack-and-nethack-the-software-distillery/ ftp://ftp.cuhk.edu.hk/pub/oldies/apple2/unsorted/Hack.txt