Merge branch 'unistd_h_in_dev' of https://github.com/rosslwheeler/llm.c into rosslwheeler-unistd_h_in_dev

dev/unistd.h

@@ -0,0 +1,21 @@
+#ifndef UNISTD_H  
+#define UNISTD_H 
+#define _CRT_SECURE_NO_WARNINGS 
+#define _USE_MATH_DEFINES 
+#include <math.h> 
+//#define gen_max_length 64 // compile as C++ to skip this VLA issue 
+#include <time.h> 
+#define CLOCK_MONOTONIC 0 
+int clock_gettime(int ignore_variable, struct timespec* tv) 
+{ 
+    return timespec_get(tv, TIME_UTC); // TODO: not sure this is the best solution. Need to review. 
+} 
+#define OMP /* turn it on */ 
+#include  <io.h> /* needed for access below */ 
+#define F_OK 0 
+#define access _access 
+
+#define TURN_OFF_FP_FAST __pragma(float_control( precise, on, push )) // Save current setting and turn on /fp:precise
+#define TURN_ON_FP_FAST  __pragma(float_control(pop)) // Restore file's default settings
+
+#endif