diff --git a/sys/src/cmd/auth/factotum/util.c b/sys/src/cmd/auth/factotum/util.c
index 31f564e5b..699a51bf5 100644
--- a/sys/src/cmd/auth/factotum/util.c
+++ b/sys/src/cmd/auth/factotum/util.c
@@ -281,7 +281,7 @@ failure(Fsstate *s, char *fmt, ...)
 		vsnprint(e, sizeof e, fmt, arg);
 		va_end(arg);
 		strecpy(s->err, s->err+sizeof(s->err), e);
-		werrstr(e);
+		errstr(e, sizeof e);
 	}
 	flog("%d: failure %s", s->seqnum, s->err);
 	return RpcFailure;
diff --git a/sys/src/cmd/auth/passwd.c b/sys/src/cmd/auth/passwd.c
index cd9c98572..20369805f 100644
--- a/sys/src/cmd/auth/passwd.c
+++ b/sys/src/cmd/auth/passwd.c
@@ -29,7 +29,7 @@ asrdresp(int fd, char *buf, int len)
 			return -1;
 		}
 		error[AERRLEN-1] = 0;
-		werrstr(error);
+		errstr(error, sizeof error);
 		return -1;
 	default:
 		werrstr(pbmsg);
diff --git a/sys/src/cmd/cec/cec.c b/sys/src/cmd/cec/cec.c
index f962a037e..90aae6217 100644
--- a/sys/src/cmd/cec/cec.c
+++ b/sys/src/cmd/cec/cec.c
@@ -196,14 +196,14 @@ timewait(int ms)
 int
 didtimeout(void)
 {
-	char buf[ERRMAX];
+	char err[ERRMAX];
+	int rv;
 
-	rerrstr(buf, sizeof buf);
-	if(strcmp(buf, "interrupted") == 0){
-		werrstr(buf, 0);
-		return 1;
-	}
-	return 0;
+	*err = 0;
+	errstr(err, sizeof err);
+	rv = strcmp(err, "interrupted") == 0;
+	errstr(err, sizeof err);
+	return rv;
 }
 
 ushort
diff --git a/sys/src/cmd/cpu.c b/sys/src/cmd/cpu.c
index 361f568b2..1bfec1764 100644
--- a/sys/src/cmd/cpu.c
+++ b/sys/src/cmd/cpu.c
@@ -443,7 +443,7 @@ rexcall(int *fd, char *host, char *service)
 		if(n < 0)
 			return "negotiating aan";
 		if(*err){
-			werrstr(err);
+			errstr(err, sizeof err);
 			return negstr;
 		}
 	}
@@ -460,7 +460,7 @@ rexcall(int *fd, char *host, char *service)
 	if(n < 0)
 		return negstr;
 	if(*err){
-		werrstr(err);
+		errstr(err, sizeof err);
 		return negstr;
 	}
 
diff --git a/sys/src/cmd/ip/ftpd.c b/sys/src/cmd/ip/ftpd.c
index 8626ab47e..1aa395b89 100644
--- a/sys/src/cmd/ip/ftpd.c
+++ b/sys/src/cmd/ip/ftpd.c
@@ -160,14 +160,11 @@ logit(char *fmt, ...)
 {
 	char buf[8192];
 	va_list arg;
-	char errstr[ERRMAX];
 
-	rerrstr(errstr, sizeof errstr);
 	va_start(arg, fmt);
 	vseprint(buf, buf+sizeof(buf), fmt, arg);
 	va_end(arg);
 	syslog(0, FTPLOG, "%s.%s %s", nci->rsys, nci->rserv, buf);
-	werrstr(errstr, sizeof errstr);
 }
 
 static void
diff --git a/sys/src/cmd/ip/ftpfs/proto.c b/sys/src/cmd/ip/ftpfs/proto.c
index 14fe56ee9..cf4cb0f99 100644
--- a/sys/src/cmd/ip/ftpfs/proto.c
+++ b/sys/src/cmd/ip/ftpfs/proto.c
@@ -1324,7 +1324,7 @@ passive(int mode, Biobuf **bpp, char *cmda, char *cmdb)
 		close(fd);
 		if(debug)
 			fprint(2, "passive mode retrieve failed: %s\n", msg);
-		werrstr(msg);
+		werrstr("%s", msg);
 		return x;
 	}
 
diff --git a/sys/src/cmd/ip/tftpfs.c b/sys/src/cmd/ip/tftpfs.c
index 7f1fcb003..fa84d2b1d 100644
--- a/sys/src/cmd/ip/tftpfs.c
+++ b/sys/src/cmd/ip/tftpfs.c
@@ -212,7 +212,7 @@ download(void *aux)
 		msg.buf[n] = 0;
 		switch(nhgets(msg.buf)){
 		case Tftp_ERROR:
-			werrstr((char*)msg.buf+4);
+			werrstr("%s", (char*)msg.buf+4);
 			err = "%r";
 			goto out;
 
diff --git a/sys/src/cmd/ip/traceroute.c b/sys/src/cmd/ip/traceroute.c
index 33b6678b2..3113d6ded 100644
--- a/sys/src/cmd/ip/traceroute.c
+++ b/sys/src/cmd/ip/traceroute.c
@@ -140,8 +140,7 @@ static int
 udpprobe(int cfd, int dfd, char *dest, int interval)
 {
 	int n, i, rv;
-	char msg[Maxstring];
-	char err[Maxstring];
+	char msg[Maxstring], err[ERRMAX];
 
 	seek(cfd, 0, 0);
 	n = snprint(msg, sizeof msg, "connect %s", dest);
@@ -166,12 +165,13 @@ udpprobe(int cfd, int dfd, char *dest, int interval)
 			rv = 0;
 			break;
 		}
+		*err = 0;
 		errstr(err, sizeof err);
-		if(strstr(err, "alarm") == 0){
-			werrstr(err);
+		if(strcmp(err, "interrupted") != 0){
+			errstr(err, sizeof err);
 			break;
 		}
-		werrstr(err);
+		errstr(err, sizeof err);
 	}
 	alarm(0);
 	return rv;
@@ -185,7 +185,7 @@ static int
 icmpprobe(int cfd, int dfd, char *dest, int interval)
 {
 	int x, i, n, len, rv;
-	char buf[512], err[Maxstring], msg[Maxstring];
+	char buf[512], err[ERRMAX], msg[Maxstring];
 	Icmphdr *ip;
 
 	seek(cfd, 0, 0);
@@ -212,12 +212,13 @@ icmpprobe(int cfd, int dfd, char *dest, int interval)
 		n = read(dfd, buf, sizeof(buf));
 		alarm(0);
 		if(n < 0){
+			*err = 0;
 			errstr(err, sizeof err);
-			if(strstr(err, "alarm") == 0){
-				werrstr(err);
+			if(strcmp(err, "interrupted") != 0){
+				errstr(err, sizeof err);
 				break;
 			}
-			werrstr(err);
+			errstr(err, sizeof err);
 			continue;
 		}
 		x = (ip->seq[1]<<8) | ip->seq[0];
@@ -337,7 +338,7 @@ main(int argc, char **argv)
 	long *t;
 	char *net, *p;
 	char clone[Maxpath], dest[Maxstring], hop[Maxstring], dom[Maxstring];
-	char err[Maxstring];
+	char err[ERRMAX];
 	DS ds;
 
 	buckets = 0;
@@ -396,6 +397,7 @@ main(int argc, char **argv)
 				done = 1;
 				continue;
 			}
+			*err = 0;
 			errstr(err, sizeof err);
 			if(strstr(err, "refused")){
 				strcpy(hop, dest);
diff --git a/sys/src/cmd/jpg/readgif.c b/sys/src/cmd/jpg/readgif.c
index 0a5edd364..d5c0d1d7d 100644
--- a/sys/src/cmd/jpg/readgif.c
+++ b/sys/src/cmd/jpg/readgif.c
@@ -93,7 +93,7 @@ giferror(Header *h, char *fmt, ...)
 	vseprint(h->err, h->err+sizeof h->err, fmt, arg);
 	va_end(arg);
 
-	werrstr(h->err);
+	werrstr("%s", h->err);
 	giffreeall(h, 1);
 	longjmp(h->errlab, 1);
 }
diff --git a/sys/src/cmd/jpg/readjpg.c b/sys/src/cmd/jpg/readjpg.c
index a3ab3ed8a..676ce2afb 100644
--- a/sys/src/cmd/jpg/readjpg.c
+++ b/sys/src/cmd/jpg/readjpg.c
@@ -227,7 +227,7 @@ jpgerror(Header *h, char *fmt, ...)
 	vseprint(h->err, h->err+sizeof h->err, fmt, arg);
 	va_end(arg);
 
-	werrstr(h->err);
+	werrstr("%s", h->err);
 	jpgfreeall(h, 1);
 	longjmp(h->errlab, 1);
 }
diff --git a/sys/src/cmd/jpg/torgbv.c b/sys/src/cmd/jpg/torgbv.c
index ca84592b4..d1cef81a3 100644
--- a/sys/src/cmd/jpg/torgbv.c
+++ b/sys/src/cmd/jpg/torgbv.c
@@ -16,13 +16,13 @@ void*
 _remaperror(char *fmt, ...)
 {
 	va_list arg;
-	char buf[256];
+	char buf[ERRMAX];
 
 	va_start(arg, fmt);
 	vseprint(buf, buf+sizeof buf, fmt, arg);
 	va_end(arg);
 
-	werrstr(buf);
+	errstr(buf, sizeof buf);
 	return nil;
 }
 
diff --git a/sys/src/cmd/rio/rio.c b/sys/src/cmd/rio/rio.c
index 5d7fe2e91..052dcaff3 100644
--- a/sys/src/cmd/rio/rio.c
+++ b/sys/src/cmd/rio/rio.c
@@ -1380,7 +1380,7 @@ initkbd(void)
 	if(e = recvp(c)){
 		chanfree(c);
 		c = nil;
-		werrstr(e);
+		werrstr("%s", e);
 		free(e);
 	}
 	return c;
diff --git a/sys/src/cmd/wikifs/io.c b/sys/src/cmd/wikifs/io.c
index 43743744e..6be5f22c5 100644
--- a/sys/src/cmd/wikifs/io.c
+++ b/sys/src/cmd/wikifs/io.c
@@ -676,7 +676,7 @@ writepage(int num, ulong t, String *s, char *title)
 	if(conflict){
 		close(lfd);
 		voidcache(num);
-		werrstr(err);
+		errstr(err, sizeof err);
 		return -1;
 	}
 
diff --git a/sys/src/libventi/client.c b/sys/src/libventi/client.c
index 40ee85175..80c03bf90 100644
--- a/sys/src/libventi/client.c
+++ b/sys/src/libventi/client.c
@@ -21,7 +21,7 @@ vtfcallrpc(VtConn *z, VtFcall *ou, VtFcall *in)
 	if(chattyventi)
 		fprint(2, "%s <- %F\n", argv0, in);
 	if(in->msgtype == VtRerror){
-		werrstr(in->error);
+		werrstr("%s", in->error);
 		vtfcallclear(in);
 		packetfree(p);
 		return -1;