From 4b5c40b637a7cba26ffbfd3827457fd40c52d422 Mon Sep 17 00:00:00 2001
From: Luxferre <lux@ferre>
Date: Thu, 18 Jan 2024 12:30:27 +0200
Subject: [PATCH] Updated README about POSIX compatibility

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 README | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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+nnfc: no-nonsense FreeCell game in under 300 SLOC of POSIX AWK
+--------------------------------------------------------------
+This is a simple and straightforward FreeCell implementation that adheres
+to the POSIX AWK standard. Within <300 SLOC, it features:
+
+* simple line-oriented command prompt compatible with standard move notation;
+* Unicode/ASCII card suit signs (Unicode by default);
+* color/monochrome display selection (color by default);
+* M$-FreeCell-compatible deal seeding by the game number;
+* FreeCell Pro-compatible supermoves to move stacks of cards between columns;
+* FreeCell Pro-compatible card autohoming ("safe autoplay" strategy);
+* internal help screen.
+
+== How to run ==
+
+The game is run as a usual AWK script:
+
+awk -f nnfc.awk [-v ASCII=1] [-v MONOCHROME=1] [-v SEED=xxxxx]
+
+Available parameters to pass to the script:
+
+* `-v ASCII=1`: display Latin letters (c, d, h, s) instead of UTF-8 suits
+* `-v MONOCHROME=1`: disable colors when displaying cards (e.g. on e-ink)
+* `-v SEED=xxxxx`: set the PRNG seed (game number) to start a predefined game
+
+== How to play ==
+
+Once run, the game shows the current seed (game) number, the playfield with
+all the cards in the traditional columnar layout and a command prompt.
+Press Enter/Return after every command entry.
+
+Move commands are entered with two characters without any separator:
+
+* 0 or h is foundation/home cell (can be omitted and can only be the second)
+* 1 to 8 are column (tableau) numbers
+* a to d are freecell IDs
+
+Examples:
+
+* 7a: move from column 7 to freecell a
+* 63: move (as many cards as possible) from column 6 to column 3
+* d1: move from freecell d to column 1
+* 4 (or 40, or 4h): move from column 4 to the foundation/home cell
+* c (or c0, or ch): move from freecell c to the foundation/home cell
+
+Besides moves, the following commands are available:
+
+* h: display a help screen
+* u: undo the last move (the history is saved from the beginning)
+* r: restart (undo to the starting playfield)
+* q: quit the game
+
+== Compatibility ==
+
+Primary testing was done on nawk and busybox awk, but the game should work
+correctly on mawk, gawk and any other POSIX-compliant AWK implementation.
+Particularly, additional tweaking had been done to make sure the game works
+correctly with gawk --posix and mawk -W posix flags.
+
+== Credits ==
+
+Created by Luxferre in 2024. Released into public domain.
+