diff --git a/lib/lib_strcspn.c b/lib/lib_strcspn.c
index 92a60fc0b0..1c18eb1223 100644
--- a/lib/lib_strcspn.c
+++ b/lib/lib_strcspn.c
@@ -58,7 +58,7 @@
  *
  ****************************************************************************/
 
-size_t strspn(const char *s, const char *reject)
+size_t strcspn(const char *s, const char *reject)
 {
   size_t i;
   for (i = 0; s[i] && strchr(reject, s[i]) == NULL; i++);