From da13ba3b8eef5cdaa36728bfc09206ea9d743668 Mon Sep 17 00:00:00 2001
From: David Griffith <dave@661.org>
Date: Tue, 23 Jul 2019 03:00:36 -0700
Subject: [PATCH] Identify host OS as Unix if so.  Include unistd.h protected
 by UNIX define.

---
 Makefile          | 5 +++++
 src/sdl/sf_util.c | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/Makefile b/Makefile
index 01766dc..d766d9d 100644
--- a/Makefile
+++ b/Makefile
@@ -13,6 +13,8 @@ CFLAGS += -Wall -std=c99 #-Wextra
 
 # Determine if we are compiling on MAC OS X
 ifneq ($(OS),Windows_NT)
+    # For now, assume !windows == unix.
+    OS_TYPE ?= unix
     UNAME_S := $(shell uname -s)
     ifeq ($(UNAME_S),Darwin)
 	MACOS = yes
@@ -306,6 +308,9 @@ $(COMMON_DEFINES):
 	@echo "** Generating $@"
 	@echo "#ifndef COMMON_DEFINES_H" > $@
 	@echo "#define COMMON_DEFINES_H" >> $@
+ifeq ($(OS_TYPE), unix)
+	@echo "#define UNIX" >> $@
+endif
 ifdef NO_BLORB
 	@echo "#define NO_BLORB" >> $@
 endif
diff --git a/src/sdl/sf_util.c b/src/sdl/sf_util.c
index 78d3b12..0ec6090 100644
--- a/src/sdl/sf_util.c
+++ b/src/sdl/sf_util.c
@@ -14,6 +14,10 @@
 #include <io.h>
 #endif
 
+#ifdef UNIX
+#include <unistd.h>
+#endif
+
 f_setup_t f_setup;
 
 typedef void (*CLEANFUNC)();
-- 
2.34.1