diff --git a/src/temp/mkdtemp.c b/src/temp/mkdtemp.c
index 76140c77..195e9cba 100644
--- a/src/temp/mkdtemp.c
+++ b/src/temp/mkdtemp.c
@@ -8,19 +8,23 @@
 #include <sys/stat.h>
 #include "libc.h"
 
-char *__mktemp(char *);
+char *__randname(char *);
 
 char *mkdtemp(char *template)
 {
-	int retries = 100, t0 = *template;
-	while (retries--) {
-		if (!*__mktemp(template)) return 0;
-		if (!mkdir(template, 0700)) return template;
-		if (errno != EEXIST) return 0;
-		/* this is safe because mktemp verified
-		 * that we have a valid template string */
-		template[0] = t0;
-		strcpy(template+strlen(template)-6, "XXXXXX");
+	size_t l = strlen(template);
+	int retries = 100;
+
+	if (l<6 || memcmp(template+l-6, "XXXXXX", 6)) {
+		errno = EINVAL;
+		return 0;
 	}
+
+	do {
+		__randname(template+l-6);
+		if (!mkdir(template, 0700)) return template;
+	} while (--retries && errno == EEXIST);
+
+	memcpy(template+l-6, "XXXXXX", 6);
 	return 0;
 }
diff --git a/src/temp/mkostemps.c b/src/temp/mkostemps.c
index 8cc01e37..7f8492a1 100644
--- a/src/temp/mkostemps.c
+++ b/src/temp/mkostemps.c
@@ -16,12 +16,13 @@ int __mkostemps(char *template, int len, int flags)
 	}
 
 	int fd, retries = 100;
-	while (retries--) {
+	do {
 		__randname(template+l-len-6);
 		if ((fd = open(template, flags | O_RDWR | O_CREAT | O_EXCL, 0600))>=0)
 			return fd;
-		if (errno != EEXIST) return -1;
-	}
+	} while (--retries && errno == EEXIST);
+
+	memcpy(template+l-len-6, "XXXXXX", 6);
 	return -1;
 }