diff --git a/magick/coder.h b/magick/coder.h
index b4ad19f..0c831a4 100644
--- a/magick/coder.h
+++ b/magick/coder.h
@@ -37,16 +37,16 @@
*previous,
*next; /* deprecated, use GetCoderInfoList() */
- unsigned long
+ size_t
signature;
} CoderInfo;
extern MagickExport char
- **GetCoderList(const char *,unsigned long *,ExceptionInfo *);
+ **GetCoderList(const char *,size_t *,ExceptionInfo *);
extern MagickExport const CoderInfo
*GetCoderInfo(const char *,ExceptionInfo *),
- **GetCoderInfoList(const char *,unsigned long *,ExceptionInfo *);
+ **GetCoderInfoList(const char *,size_t *,ExceptionInfo *);
extern MagickExport MagickBooleanType
CoderComponentGenesis(void),