diff --git a/du.c b/du.c
index 304fee1..8382178 100644
--- a/du.c
+++ b/du.c
@@ -120,6 +120,7 @@ du(const char *path)
 	struct dirent *dent;
 	struct stat st;
 	long n = 0, m;
+	int r;
 
 	if (lstat(path, &st) < 0)
 		eprintf("stat: %s:", path);
@@ -149,8 +150,9 @@ du(const char *path)
 		n += m;
 		if (aflag && !sflag) {
 			if (S_ISLNK(st.st_mode)) {
-				if (snprintf(file, sizeof(file), "%s/%s",
-					     cwd, dent->d_name) >= sizeof(file))
+				r = snprintf(file, sizeof(file), "%s/%s",
+					     cwd, dent->d_name);
+				if(r >= sizeof(file) || r < 0)
 					eprintf("path too long\n");
 			} else {
 				xrealpath(dent->d_name, file);
diff --git a/mktemp.c b/mktemp.c
index cf2572f..e001dac 100644
--- a/mktemp.c
+++ b/mktemp.c
@@ -21,7 +21,7 @@ main(int argc, char *argv[])
 	char *template = "tmp.XXXXXXXXXX";
 	char *tmpdir = "/tmp", *p;
 	char tmppath[PATH_MAX];
-	int fd;
+	int fd, r;
 
 	ARGBEGIN {
 	case 'd':
@@ -42,8 +42,9 @@ main(int argc, char *argv[])
 	if ((p = getenv("TMPDIR")))
 		tmpdir = p;
 
-	if (snprintf(tmppath, sizeof(tmppath),
-		     "%s/%s", tmpdir, template) >= sizeof(tmppath))
+	r = snprintf(tmppath, sizeof(tmppath),
+		     "%s/%s", tmpdir, template);
+	if (r >= sizeof(tmppath) || r < 0)
 		eprintf("path too long\n");
 	if (dflag) {
 		if (!mkdtemp(tmppath)) {
diff --git a/util/cp.c b/util/cp.c
index e8627cd..753e616 100644
--- a/util/cp.c
+++ b/util/cp.c
@@ -24,6 +24,7 @@ cp(const char *s1, const char *s2)
 	struct dirent *d;
 	struct stat st;
 	DIR *dp;
+	int r;
 
 	if (stat(s1, &st) == 0 && S_ISDIR(st.st_mode)) {
 		if (!cp_rflag)
@@ -40,14 +41,13 @@ cp(const char *s1, const char *s2)
 		while((d = readdir(dp))) {
 			if(strcmp(d->d_name, ".")
 			   && strcmp(d->d_name, "..")) {
-				if(snprintf(ns1, size1, "%s/%s", s1,
-					    d->d_name) >= size1) {
+				r = snprintf(ns1, size1, "%s/%s", s1, d->d_name);
+				if(r >= size1 || r < 0) {
 					eprintf("%s/%s: filename too long\n",
 						s1, d->d_name);
 				}
-
-				if(snprintf(ns2, size2, "%s/%s", s2,
-					    d->d_name) >= size2) {
+				r = snprintf(ns2, size2, "%s/%s", s2, d->d_name);
+				if(r >= size2 || r < 0) {
 					eprintf("%s/%s: filename too long\n",
 						s2, d->d_name);
 				}