--- ray/src/common/standard.h	1995/11/10 17:04:14	2.6
+++ ray/src/common/standard.h	1996/01/17 10:54:46	2.8
@@ -26,11 +26,13 @@ typedef struct {
 	XF  b;					/* backward */
 }  FULLXF;
 
+#ifndef  PI
 #ifdef	M_PI
 #define	 PI		M_PI
 #else
 #define	 PI		3.14159265358979323846
 #endif
+#endif
 
 #ifndef	 F_OK			/* mode bits for access(2) call */
 #define	 R_OK		4		/* readable */
@@ -63,7 +65,7 @@ extern char  errmsg[];			/* global buffer for error me
 #define	 rindex			strrchr
 #endif
 
-extern char  *sskip();
+extern char  *sskip(), *sskip2();
 extern char  *getpath(), *getenv();
 #ifndef malloc
 extern char  *malloc(), *calloc(), *realloc();