diff --git a/cbmarcs.c b/cbmarcs.c
index 793f6d9..08d3e77 100644
--- a/cbmarcs.c
+++ b/cbmarcs.c
@@ -331,7 +331,7 @@ bool IsC64_ARC(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirARC(FILE *InFile, enum ArchiveTypes ArcType,	struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	long CurrentPos;
 
@@ -567,7 +567,7 @@ bool IsLynxNew(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirLynx(FILE *InFile, enum ArchiveTypes LynxType, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	int NumFiles;
 	char LynxVer[10];
@@ -814,7 +814,7 @@ bool IsLHA(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirLHA(FILE *InFile, enum ArchiveTypes LHAType, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	long CurrentPos;
 
@@ -962,7 +962,7 @@ bool IsT64(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirT64(FILE *InFile, enum ArchiveTypes ArchiveType, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	char TapeName[25];
 	int NumFiles;
@@ -1403,7 +1403,7 @@ bool IsC1581(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirD64(FILE *InFile, enum ArchiveTypes D64Type, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	char DiskLabel[24];  /* Holds the disk label plus filler, version and format */
 	long CurrentPos;
@@ -1741,7 +1741,7 @@ bool IsR00(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirP00(FILE *InFile, enum ArchiveTypes ArchiveType, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	long FileLength;
 	char FileName[17];
@@ -1850,7 +1850,7 @@ bool IsN64(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirN64(FILE *InFile, enum ArchiveTypes ArchiveType, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	long FileLength;
 	char FileName[17];
@@ -1931,7 +1931,7 @@ bool IsLBR(FILE *InFile, const char *FileName)
 * Read directory
 ******************************************************************************/
 int DirLBR(FILE *InFile, enum ArchiveTypes LBRType, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	int NumFiles;
 
@@ -2200,7 +2200,7 @@ int CheckTapeHeader(struct TapeHeader *Header, int Len, int Which)
 }
 
 int DirTAP(FILE *InFile, enum ArchiveTypes ArchiveType, struct ArcTotals *Totals,
-		int (*DisplayStart)(), int (*DisplayEntry)())
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	struct TAPHeader FileHeader;
 	LONG Flen;
@@ -2615,10 +2615,7 @@ bool (* const DirFunctions[])() = {
 ******************************************************************************/
 int DirArchive(FILE *InFile, enum ArchiveTypes ArchiveType,
 		struct ArcTotals *Totals,
-		void (*DisplayStart)(enum ArchiveTypes ArchiveType, const char *Name),
-		int (*DisplayEntry)(const char *Name, const char *Type, unsigned long Length,
-			unsigned Blocks, const char *Storage, int Compression,
-			unsigned BlocksNow, long Checksum))
+		DisplayStartFunc DisplayStart, DisplayEntryFunc DisplayEntry)
 {
 	if (ArchiveType >= UnknownArchive)
 		return 3;
diff --git a/cbmarcs.h b/cbmarcs.h
index 2c7c784..c03cd8c 100644
--- a/cbmarcs.h
+++ b/cbmarcs.h
@@ -117,9 +117,10 @@ struct ArcTotals {
 
 
 enum ArchiveTypes DetermineArchiveType(FILE *InFile, const char *FileName);
+
+typedef void (*DisplayStartFunc)(enum ArchiveTypes ArchiveType, const char *Name);
+typedef	int (*DisplayEntryFunc)(const char *Name, const char *Type,
+			unsigned long Length, unsigned Blocks, const char *Storage,
+			int Compression, unsigned BlocksNow, long Checksum);
 int DirArchive(FILE *InFile, enum ArchiveTypes SDAType,
-		struct ArcTotals *Totals,
-		void (*DisplayStart)(enum ArchiveTypes ArchiveType, const char *Name),
-		int (*DisplayEntry)(const char *Name, const char *Type, unsigned long Length,
-			unsigned Blocks, const char *Storage, int Compression,
-			unsigned BlocksNow, long Checksum));
+		struct ArcTotals *Totals, DisplayStartFunc, DisplayEntryFunc);