diff --git a/wav.c b/wav.c
index d72493e..812ce9a 100755
--- a/wav.c
+++ b/wav.c
@@ -44,7 +44,7 @@ uint32_t WavSetFormat(struct _sWAV *pObj, uint32_t nSamplesPerSec, uint16_t nBit
 }
 
 /******************************************************************************/
-uint32_t WavOpen (struct _sWAV *pObj, char* FileName)
+uint32_t WavOpen (struct _sWAV *pObj, const char* FileName)
 {
 	uint32_t stat;
 
diff --git a/wav.h b/wav.h
index 646eb93..c1cb58a 100755
--- a/wav.h
+++ b/wav.h
@@ -52,7 +52,7 @@ extern "C" {
 
 void WavInit(struct _sWAV*, uint32_t nSamplesPerSec, uint16_t nBits, uint16_t nChannels, uint16_t format);
 uint32_t WavSetFormat(struct _sWAV*, uint32_t, uint16_t, uint16_t, uint16_t format);
-uint32_t WavOpen (struct _sWAV*, char*);
+uint32_t WavOpen (struct _sWAV*, const char*);
 uint32_t WavCreate(struct _sWAV*, char*, uint32_t);
 uint32_t WavClose(struct _sWAV*);
 uint32_t WavRead(struct _sWAV*, void*, uint32_t);