diff --git a/sys/src/cmd/mothra/rdhtml.c b/sys/src/cmd/mothra/rdhtml.c
index 201959762..0fb528a7f 100644
--- a/sys/src/cmd/mothra/rdhtml.c
+++ b/sys/src/cmd/mothra/rdhtml.c
@@ -243,7 +243,7 @@ char *unquot(char *dst, char *src, int len){
 	char *e;
 
 	e=0;
-	while(strchr("\n\r\t ", *src))
+	while(*src && strchr(" \t\r\n", *src))
 		src++;
 	if(*src=='\'' || *src=='"'){
 		e=strrchr(src+1, *src);
diff --git a/sys/src/cmd/uhtml.c b/sys/src/cmd/uhtml.c
index 6c9de188e..9d7ef4422 100644
--- a/sys/src/cmd/uhtml.c
+++ b/sys/src/cmd/uhtml.c
@@ -5,6 +5,7 @@
 int nbuf;
 char buf[64*1024+1];
 char *cset = nil;
+char *whitespace = " \t\r\n";
 
 void
 usage(void)
@@ -21,11 +22,11 @@ attr(char *s, char *a)
 	if((s = cistrstr(s, a)) == nil)
 		return nil;
 	s += strlen(a);
-	while(strchr("\r\n\t ", *s))
+	while(*s && strchr(whitespace, *s))
 		s++;
 	if(*s++ != '=')
 		return nil;
-	while(strchr("\r\n\t ", *s))
+	while(*s && strchr(whitespace, *s))
 		s++;
 	q = 0;
 	if(*s == '"' || *s == '\'')
diff --git a/sys/src/cmd/webfs/dat.h b/sys/src/cmd/webfs/dat.h
index 60dd0870c..b6aab58e8 100644
--- a/sys/src/cmd/webfs/dat.h
+++ b/sys/src/cmd/webfs/dat.h
@@ -67,3 +67,4 @@ struct Buq
 int	debug;
 Url	*proxy;
 int	timeout;
+char	*whitespace;
diff --git a/sys/src/cmd/webfs/fs.c b/sys/src/cmd/webfs/fs.c
index 5e803d07d..b513ec114 100644
--- a/sys/src/cmd/webfs/fs.c
+++ b/sys/src/cmd/webfs/fs.c
@@ -613,7 +613,7 @@ clientctl(Client *cl, char *ctl, char *arg)
 	else if(!strcmp(ctl, "headers")){
 		while(arg && *arg){
 			ctl = arg;
-			while(*ctl && strchr("\r\n\t ", *ctl))
+			while(*ctl && strchr(whitespace, *ctl))
 				ctl++;
 			if(arg = strchr(ctl, '\n'))
 				*arg++ = 0;
@@ -663,9 +663,9 @@ fswrite(Req *r)
 			n--;
 		s[n] = 0;
 		t = s;
-		while(*t && strchr("\r\n\t ", *t)==0)
+		while(*t && strchr(whitespace, *t)==0)
 			t++;
-		while(*t && strchr("\r\n\t ", *t))
+		while(*t && strchr(whitespace, *t))
 			*t++ = 0;
 		if(f->level == Qctl)
 			t = clientctl(f->client, s, t);
diff --git a/sys/src/cmd/webfs/http.c b/sys/src/cmd/webfs/http.c
index 6562b9815..04882b138 100644
--- a/sys/src/cmd/webfs/http.c
+++ b/sys/src/cmd/webfs/http.c
@@ -274,9 +274,9 @@ hline(Hconn *h, char *data, int len, int cont)
 				if(n > 0 && cont){
 					e = h->buf + h->len;
 					for(y = x+1; y < e; y++)
-						if(!strchr("\t ", *y))
+						if(*y != ' ' && *y != '\t')
 							break;
-					if(y >= e || strchr("\t ", *y))
+					if(y >= e || *y == 0)
 						break;
 					if(y > x+1){
 						if(x > h->buf && x[-1] == '\r')
diff --git a/sys/src/cmd/webfs/sub.c b/sys/src/cmd/webfs/sub.c
index b8ca1e3ac..476e5fd26 100644
--- a/sys/src/cmd/webfs/sub.c
+++ b/sys/src/cmd/webfs/sub.c
@@ -8,6 +8,8 @@
 #include "dat.h"
 #include "fns.h"
 
+char *whitespace = " \t\r\n";
+
 void*
 emalloc(int n)
 {
@@ -85,12 +87,14 @@ parsehdr(char *s)
 {
 	char *v;
 
+	if(*s == 0)
+		return nil;
 	v = strchr(s, 0)-1;
-	while(v >= s && strchr("\n\r\t ", *v))
+	while(v >= s && strchr(whitespace, *v))
 		*v-- = 0;
 	if(v = strchr(s, ':')){
 		*v++ = 0;
-		while(strchr("\t ", *v))
+		while(*v == ' ' || *v == '\t')
 			v++;
 		if(*s && *v)
 			return addkey(0, s, v);