diff --git a/libs/libc/string/Make.defs b/libs/libc/string/Make.defs
index 39839d3b5d6..1836eeff643 100644
--- a/libs/libc/string/Make.defs
+++ b/libs/libc/string/Make.defs
@@ -25,7 +25,7 @@ CSRCS += lib_flsll.c lib_isbasedigit.c
 CSRCS += lib_memccpy.c lib_memcmp.c lib_memrchr.c
 CSRCS += lib_popcount.c lib_popcountl.c lib_popcountll.c
 CSRCS += lib_skipspace.c lib_stpcpy.c lib_stpncpy.c lib_strcasecmp.c
-CSRCS += lib_strcat.c lib_strchr.c lib_strcspn.c
+CSRCS += lib_strcat.c lib_strchr.c lib_strchrnul.c lib_strcspn.c
 CSRCS += lib_strdup.c lib_strerror.c lib_strnlen.c
 CSRCS += lib_strncasecmp.c lib_strncat.c lib_strncmp.c lib_strncpy.c
 CSRCS += lib_strndup.c lib_strcasestr.c lib_strpbrk.c lib_strrchr.c
diff --git a/libs/libc/string/lib_strchrnul.c b/libs/libc/string/lib_strchrnul.c
new file mode 100644
index 00000000000..851fcbf20d2
--- /dev/null
+++ b/libs/libc/string/lib_strchrnul.c
@@ -0,0 +1,58 @@
+/****************************************************************************
+ * libs/libc/string/lib_strchrnul.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <string.h>
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: strchrnul
+ *
+ * Description:
+ *   The strchrnul() function locates the first occurrence of 'c' (converted
+ *   to a char) in the string pointed to by 's'. The terminating null byte is
+ *   considered to be part of the string.
+ *
+ * Returned Value:
+ *   Upon completion, strchrnull() returns a pointer to the byte, or a
+ *   pointer to null if the byte was not found.
+ *
+ ****************************************************************************/
+
+FAR char *strchrnul(FAR const char *s, int c)
+{
+  if (s)
+    {
+      while (*s && *s != c)
+        {
+          s++;
+        }
+    }
+
+  return s;
+}