--- ray/src/common/calfunc.c	1991/11/12 16:55:16	2.1
+++ ray/src/common/calfunc.c	1992/05/21 10:29:32	2.4
@@ -88,8 +88,6 @@ static int  libsize = 5;
 
 extern char  *savestr(), *emalloc();
 
-extern LIBR  *liblookup();
-
 extern VARDEF  *argf();
 
 #ifdef  VARIABLE
@@ -157,7 +155,7 @@ double  (*fptr)();
 {
     register LIBR  *lp;
 
-    if ((lp = liblookup(fname)) == NULL) {
+    if ((lp = liblookup(fname)) == NULL) {	/* insert */
 	if (libsize >= MAXLIB) {
 	    eputs("Too many library functons!\n");
 	    quit(1);
@@ -172,10 +170,22 @@ double  (*fptr)();
 		break;
 	libsize++;
     }
-    lp[0].fname = fname;		/* must be static! */
-    lp[0].nargs = nargs;
-    lp[0].atyp = assign;
-    lp[0].f = fptr;
+    if (fptr == NULL) {				/* delete */
+	while (lp < &library[libsize-1]) {
+	    lp[0].fname = lp[1].fname;
+	    lp[0].nargs = lp[1].nargs;
+	    lp[0].atyp = lp[1].atyp;
+	    lp[0].f = lp[1].f;
+	    lp++;
+	}
+	libsize--;
+    } else {					/* or assign */
+	lp[0].fname = fname;		/* string must be static! */
+	lp[0].nargs = nargs;
+	lp[0].atyp = assign;
+	lp[0].f = fptr;
+    }
+    libupdate(fname);			/* relink library */
 }
 
 
@@ -327,6 +337,9 @@ char  *fname;
 
 
 #ifndef  VARIABLE
+static VARDEF  *varlist = NULL;		/* our list of dummy variables */
+
+
 VARDEF *
 varinsert(vname)		/* dummy variable insert */
 char  *vname;
@@ -337,8 +350,9 @@ char  *vname;
     vp->name = savestr(vname);
     vp->nlinks = 1;
     vp->def = NULL;
-    vp->lib = NULL;
-    vp->next = NULL;
+    vp->lib = liblookup(vname);
+    vp->next = varlist;
+    varlist = vp;
     return(vp);
 }
 
@@ -346,9 +360,28 @@ char  *vname;
 varfree(vp)			/* free dummy variable */
 register VARDEF  *vp;
 {
+    register VARDEF  *vp2;
+
+    if (vp == varlist)
+	varlist = vp->next;
+    else {
+	for (vp2 = varlist; vp2->next != vp; vp2 = vp2->next)
+		;
+	vp2->next = vp->next;
+    }
     freestr(vp->name);
     efree((char *)vp);
 }
+
+
+libupdate(nm)			/* update library */
+char  *nm;
+{
+    register VARDEF  *vp;
+
+    for (vp = varlist; vp != NULL; vp = vp->next)
+	vp->lib = liblookup(vp->name);
+}
 #endif
 
 
@@ -361,26 +394,24 @@ register VARDEF  *vp;
 static double
 libfunc(fname, vp)			/* execute library function */
 char  *fname;
-register VARDEF  *vp;
+VARDEF  *vp;
 {
-    VARDEF  dumdef;
+    register LIBR  *lp;
     double  d;
     int  lasterrno;
 
-    if (vp == NULL) {
-	vp = &dumdef;
-	vp->lib = NULL;
-    }
-    if (((vp->lib == NULL || strcmp(fname, vp->lib->fname)) &&
-				(vp->lib = liblookup(fname)) == NULL) ||
-		vp->lib->f == NULL) {
+    if (vp != NULL)
+	lp = vp->lib;
+    else
+	lp = liblookup(fname);
+    if (lp == NULL) {
 	eputs(fname);
 	eputs(": undefined function\n");
 	quit(1);
     }
     lasterrno = errno;
     errno = 0;
-    d = (*vp->lib->f)(vp->lib->fname);
+    d = (*lp->f)(lp->fname);
 #ifdef  IEEE
     if (errno == 0)
 	if (isnan(d))