changed enum type name to `ZSTD_ErrorCode`
diff --git a/lib/zstd_decompress.c b/lib/zstd_decompress.c
index 1e8aa4c..529f1b6 100644
--- a/lib/zstd_decompress.c
+++ b/lib/zstd_decompress.c
@@ -111,7 +111,7 @@
 
 /*! ZSTD_getError() :
 *   convert a `size_t` function result into a proper ZSTD_errorCode enum */
-ZSTD_errorCode ZSTD_getError(size_t code) { return ERR_getError(code); }
+ZSTD_ErrorCode ZSTD_getError(size_t code) { return ERR_getError(code); }
 
 /*! ZSTD_getErrorName() :
 *   provides error code string (useful for debugging) */
@@ -173,7 +173,7 @@
 size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx)
 {
     free(dctx);
-    return 0;
+    return 0;   /* reserved as a potential error code in the future */
 }
 
 void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx)