diff --git a/cyassl/ctaocrypt/port.h b/cyassl/ctaocrypt/port.h
index 945e30a47..5741c255e 100644
--- a/cyassl/ctaocrypt/port.h
+++ b/cyassl/ctaocrypt/port.h
@@ -111,6 +111,7 @@ CYASSL_LOCAL int LockMutex(CyaSSL_Mutex*);
 CYASSL_LOCAL int UnLockMutex(CyaSSL_Mutex*);
 
 
+/* filesystem abstraction layer, used by ssl.c */
 #ifndef NO_FILESYSTEM
 
 #if defined(EBSNET)
diff --git a/cyassl/ssl.h b/cyassl/ssl.h
index b1f56bc77..7821cefd2 100644
--- a/cyassl/ssl.h
+++ b/cyassl/ssl.h
@@ -619,7 +619,7 @@ enum {
 
 /* extras end */
 
-#ifndef NO_FILESYSTEM
+#if !defined(NO_FILESYSTEM) && !defined(NO_STDIO_FILESYSTEM)
 /* CyaSSL extension, provide last error from SSL_get_error
    since not using thread storage error queue */
 CYASSL_API void  CyaSSL_ERR_print_errors_fp(FILE*, int err);
@@ -824,8 +824,10 @@ CYASSL_API char* CyaSSL_X509_get_next_altname(CYASSL_X509*);
 CYASSL_API CYASSL_X509*
     CyaSSL_X509_d2i(CYASSL_X509** x509, const unsigned char* in, int len);
 #ifndef NO_FILESYSTEM
-CYASSL_API CYASSL_X509*
-    CyaSSL_X509_d2i_fp(CYASSL_X509** x509, FILE* file);
+    #ifndef NO_STDIO_FILESYSTEM
+    CYASSL_API CYASSL_X509*
+        CyaSSL_X509_d2i_fp(CYASSL_X509** x509, FILE* file);
+    #endif
 CYASSL_API CYASSL_X509*
     CyaSSL_X509_load_certificate_file(const char* fname, int format);
 #endif
diff --git a/src/ssl.c b/src/ssl.c
index 07e79a161..3bbeeff37 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -1231,7 +1231,7 @@ int CyaSSL_KeyPemToDer(const unsigned char* pem, int pemSz, unsigned char* buff,
 
 
 
-#ifndef NO_FILESYSTEM
+#if !defined(NO_FILESYSTEM) && !defined(NO_STDIO_FILESYSTEM)
 
 void CyaSSL_ERR_print_errors_fp(FILE* fp, int err)
 {
@@ -7877,6 +7877,8 @@ CYASSL_X509* CyaSSL_X509_d2i(CYASSL_X509** x509, const byte* in, int len)
 
 #ifndef NO_FILESYSTEM
 
+#ifndef NO_STDIO_FILESYSTEM
+
 CYASSL_X509* CyaSSL_X509_d2i_fp(CYASSL_X509** x509, XFILE file)
 {
     CYASSL_X509* newX509 = NULL;
@@ -7906,6 +7908,8 @@ CYASSL_X509* CyaSSL_X509_d2i_fp(CYASSL_X509** x509, XFILE file)
     return newX509;
 }
 
+#endif /* NO_STDIO_FILESYSTEM */
+
 CYASSL_X509* CyaSSL_X509_load_certificate_file(const char* fname, int format)
 {
     byte staticBuffer[FILE_BUFFER_SIZE];