diff --git a/programs/x509/cert_req.c b/programs/x509/cert_req.c
index 30df216..8b47138 100644
--- a/programs/x509/cert_req.c
+++ b/programs/x509/cert_req.c
@@ -29,8 +29,11 @@
 #include "mbedtls/platform.h"
 #else
 #include <stdio.h>
-#define mbedtls_printf     printf
-#endif
+#include <stdlib.h>
+#define mbedtls_printf          printf
+#define MBEDTLS_EXTI_SUCCESS    EXIT_SUCCESS
+#define MBEDTLS_EXIT_FAILURE    EXIT_FAILURE
+#endif /* MBEDTLS_PLATFORM_C */
 
 #if !defined(MBEDTLS_X509_CSR_WRITE_C) || !defined(MBEDTLS_FS_IO) ||  \
     !defined(MBEDTLS_PK_PARSE_C) || !defined(MBEDTLS_SHA256_C) || \
@@ -133,7 +136,8 @@
 
 int main( int argc, char *argv[] )
 {
-    int ret = 0;
+    int ret = 1;
+    int exit_code = MBEDTLS_EXIT_FAILURE;
     mbedtls_pk_context key;
     char buf[1024];
     int i;
@@ -156,7 +160,6 @@
     {
     usage:
         mbedtls_printf( USAGE );
-        ret = 1;
         goto exit;
     }
 
@@ -317,9 +320,11 @@
 
     mbedtls_printf( " ok\n" );
 
+    exit_code = MBEDTLS_EXIT_SUCCESS;
+
 exit:
 
-    if( ret != 0 && ret != 1)
+    if( exit_code != MBEDTLS_EXIT_SUCCESS )
     {
 #ifdef MBEDTLS_ERROR_C
         mbedtls_strerror( ret, buf, sizeof( buf ) );
@@ -339,7 +344,7 @@
     fflush( stdout ); getchar();
 #endif
 
-    return( ret );
+    return( exit_code );
 }
 #endif /* MBEDTLS_X509_CSR_WRITE_C && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO &&
           MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_PEM_WRITE_C */