diff --git a/src/GLOBGLUE.c b/src/GLOBGLUE.c
index a080c17..ecb1947 100644
--- a/src/GLOBGLUE.c
+++ b/src/GLOBGLUE.c
@@ -302,10 +302,10 @@ GLOBALPROC DoReportAbnormalID(uint16_t id
 
 
 #if IncludeExtnPbufs
-LOCALFUNC tMacErr PbufTransferVM(CPTR Buffera,
+LOCALFUNC MacErr_t PbufTransferVM(CPTR Buffera,
 	tPbuf i, uint32_t offset, uint32_t count, bool IsWrite)
 {
-	tMacErr result;
+	MacErr_t result;
 	uint32_t contig;
 	uint8_t * Buffer;
 
@@ -342,7 +342,7 @@ label_1:
 #if IncludeExtnPbufs
 LOCALPROC ExtnParamBuffers_Access(CPTR p)
 {
-	tMacErr result = mnvm_controlErr;
+	MacErr_t result = mnvm_controlErr;
 
 	switch (get_vm_word(p + ExtnDat_commnd)) {
 		case kCmndVersion:
@@ -423,7 +423,7 @@ LOCALPROC ExtnParamBuffers_Access(CPTR p)
 #if IncludeExtnHostTextClipExchange
 LOCALPROC ExtnHostTextClipExchange_Access(CPTR p)
 {
-	tMacErr result = mnvm_controlErr;
+	MacErr_t result = mnvm_controlErr;
 
 	switch (get_vm_word(p + ExtnDat_commnd)) {
 		case kCmndVersion:
@@ -475,7 +475,7 @@ LOCALPROC ExtnHostTextClipExchange_Access(CPTR p)
 
 LOCALPROC ExtnFind_Access(CPTR p)
 {
-	tMacErr result = mnvm_controlErr;
+	MacErr_t result = mnvm_controlErr;
 
 	switch (get_vm_word(p + ExtnDat_commnd)) {
 		case kCmndVersion:
diff --git a/src/HW/DISK/SONYEMDV.c b/src/HW/DISK/SONYEMDV.c
index ae362db..e213298 100644
--- a/src/HW/DISK/SONYEMDV.c
+++ b/src/HW/DISK/SONYEMDV.c
@@ -68,9 +68,9 @@ LOCALFUNC bool vSonyNextPendingInsert0(tDrive *Drive_No)
 	return false;
 }
 
-LOCALFUNC tMacErr CheckReadableDrive(tDrive Drive_No)
+LOCALFUNC MacErr_t CheckReadableDrive(tDrive Drive_No)
 {
-	tMacErr result;
+	MacErr_t result;
 
 	if (Drive_No >= NumDrives) {
 		result = mnvm_nsDrvErr;
@@ -83,7 +83,7 @@ LOCALFUNC tMacErr CheckReadableDrive(tDrive Drive_No)
 	return result;
 }
 
-LOCALFUNC tMacErr vSonyTransferVM(bool IsWrite,
+LOCALFUNC MacErr_t vSonyTransferVM(bool IsWrite,
 	CPTR Buffera, tDrive Drive_No,
 	uint32_t Sony_Start, uint32_t Sony_Count, uint32_t *Sony_ActCount)
 {
@@ -92,7 +92,7 @@ LOCALFUNC tMacErr vSonyTransferVM(bool IsWrite,
 		into account that the emulated memory may not be contiguous in
 		real memory. (Though it generally is for macintosh emulation.)
 	*/
-	tMacErr result;
+	MacErr_t result;
 	uint32_t contig;
 	uint32_t actual;
 	uint8_t * Buffer;
@@ -176,10 +176,10 @@ LOCALVAR uint32_t ImageTagOffset[NumDrives];
 #define ChecksumBlockSize 1024
 
 #if Sony_SupportDC42 && Sony_WantChecksumsUpdated
-LOCALFUNC tMacErr DC42BlockChecksum(tDrive Drive_No,
+LOCALFUNC MacErr_t DC42BlockChecksum(tDrive Drive_No,
 	uint32_t Sony_Start, uint32_t Sony_Count, uint32_t *r)
 {
-	tMacErr result;
+	MacErr_t result;
 	uint32_t n;
 	uint8_t Buffer[ChecksumBlockSize];
 	uint8_t *p;
@@ -237,7 +237,7 @@ LOCALPROC Drive_UpdateChecksums(tDrive Drive_No)
 #if Sony_SupportDC42
 		if (kDC42offset_userData == DataOffset) {
 			/* a disk copy 4.2 image */
-			tMacErr result;
+			MacErr_t result;
 			uint32_t dataChecksum;
 			uint8_t Buffer[SizeCheckSumsToUpdate];
 			uint32_t Sony_Count = SizeCheckSumsToUpdate;
@@ -291,10 +291,10 @@ LOCALPROC Drive_UpdateChecksums(tDrive Drive_No)
 
 #define Sony_SupportOtherFormats Sony_SupportDC42
 
-LOCALFUNC tMacErr vSonyNextPendingInsert(tDrive *Drive_No)
+LOCALFUNC MacErr_t vSonyNextPendingInsert(tDrive *Drive_No)
 {
 	tDrive i;
-	tMacErr result;
+	MacErr_t result;
 	uint32_t L;
 
 	if (! vSonyNextPendingInsert0(&i)) {
@@ -469,11 +469,11 @@ GLOBALPROC Sony_Update (void)
 	}
 }
 
-LOCALFUNC tMacErr Drive_Transfer(bool IsWrite, CPTR Buffera,
+LOCALFUNC MacErr_t Drive_Transfer(bool IsWrite, CPTR Buffera,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
-	tMacErr result;
+	MacErr_t result;
 
 	QuietEnds();
 
@@ -517,9 +517,9 @@ GLOBALPROC Sony_SetQuitOnEject(void)
 	QuitOnEject = true;
 }
 
-LOCALFUNC tMacErr Drive_Eject(tDrive Drive_No)
+LOCALFUNC MacErr_t Drive_Eject(tDrive Drive_No)
 {
-	tMacErr result;
+	MacErr_t result;
 
 	result = CheckReadableDrive(Drive_No);
 	if (mnvm_noErr == result) {
@@ -539,9 +539,9 @@ LOCALFUNC tMacErr Drive_Eject(tDrive Drive_No)
 }
 
 #if IncludeSonyNew
-LOCALFUNC tMacErr Drive_EjectDelete(tDrive Drive_No)
+LOCALFUNC MacErr_t Drive_EjectDelete(tDrive Drive_No)
 {
-	tMacErr result;
+	MacErr_t result;
 
 	result = CheckReadableDrive(Drive_No);
 	if (mnvm_noErr == result) {
@@ -619,7 +619,7 @@ GLOBALPROC Sony_Reset(void)
 
 GLOBALPROC ExtnDisk_Access(CPTR p)
 {
-	tMacErr result = mnvm_controlErr;
+	MacErr_t result = mnvm_controlErr;
 
 	switch (get_vm_word(p + ExtnDat_commnd)) {
 		case kCmndVersion:
@@ -944,10 +944,10 @@ LOCALFUNC uint32_t DriveVarsLocation(tDrive Drive_No)
 	}
 }
 
-LOCALFUNC tMacErr Sony_Mount(CPTR p)
+LOCALFUNC MacErr_t Sony_Mount(CPTR p)
 {
 	uint32_t data = get_vm_long(p + ExtnDat_params + 0);
-	tMacErr result = mnvm_miscErr;
+	MacErr_t result = mnvm_miscErr;
 	tDrive i = data & 0x0000FFFF;
 	CPTR dvl = DriveVarsLocation(i);
 
@@ -1035,10 +1035,10 @@ LOCALFUNC tMacErr Sony_Mount(CPTR p)
 }
 
 #if Sony_SupportTags
-LOCALFUNC tMacErr Sony_PrimeTags(tDrive Drive_No,
+LOCALFUNC MacErr_t Sony_PrimeTags(tDrive Drive_No,
 	uint32_t Sony_Start, uint32_t Sony_Count, bool IsWrite)
 {
-	tMacErr result = mnvm_noErr;
+	MacErr_t result = mnvm_noErr;
 	uint32_t TagOffset = ImageTagOffset[Drive_No];
 
 	if ((0 != TagOffset) && (Sony_Count > 0)) {
@@ -1084,9 +1084,9 @@ label_fail:
 #endif
 
 /* Handles I/O to disks */
-LOCALFUNC tMacErr Sony_Prime(CPTR p)
+LOCALFUNC MacErr_t Sony_Prime(CPTR p)
 {
-	tMacErr result;
+	MacErr_t result;
 	uint32_t Sony_Count;
 	uint32_t Sony_Start;
 	uint32_t Sony_ActCount = 0;
@@ -1240,9 +1240,9 @@ label_fail:
 }
 
 /* Implements control csCodes for the Sony driver */
-LOCALFUNC tMacErr Sony_Control(CPTR p)
+LOCALFUNC MacErr_t Sony_Control(CPTR p)
 {
-	tMacErr result;
+	MacErr_t result;
 	CPTR ParamBlk = get_vm_long(p + ExtnDat_params + 0);
 	/* CPTR DeviceCtl = get_vm_long(p + ExtnDat_params + 4); */
 	uint16_t OpCode = get_vm_word(ParamBlk + kcsCode);
@@ -1429,9 +1429,9 @@ LOCALFUNC tMacErr Sony_Control(CPTR p)
 }
 
 /* Handles the DriveStatus call */
-LOCALFUNC tMacErr Sony_Status(CPTR p)
+LOCALFUNC MacErr_t Sony_Status(CPTR p)
 {
-	tMacErr result;
+	MacErr_t result;
 	CPTR ParamBlk = get_vm_long(p + ExtnDat_params + 0);
 	/* CPTR DeviceCtl = get_vm_long(p + ExtnDat_params + 4); */
 	uint16_t OpCode = get_vm_word(ParamBlk + kcsCode);
@@ -1473,7 +1473,7 @@ LOCALFUNC tMacErr Sony_Status(CPTR p)
 	return result;
 }
 
-LOCALFUNC tMacErr Sony_Close(CPTR p)
+LOCALFUNC MacErr_t Sony_Close(CPTR p)
 {
 #if 0
 	CPTR ParamBlk = get_vm_long(p + ExtnDat_params + 0);
@@ -1483,7 +1483,7 @@ LOCALFUNC tMacErr Sony_Close(CPTR p)
 	return mnvm_closErr; /* Can't Close Driver */
 }
 
-LOCALFUNC tMacErr Sony_OpenA(CPTR p)
+LOCALFUNC MacErr_t Sony_OpenA(CPTR p)
 {
 #if Sony_dolog
 	dbglog_WriteNote("Sony : OpenA");
@@ -1504,7 +1504,7 @@ LOCALFUNC tMacErr Sony_OpenA(CPTR p)
 	}
 }
 
-LOCALFUNC tMacErr Sony_OpenB(CPTR p)
+LOCALFUNC MacErr_t Sony_OpenB(CPTR p)
 {
 	int16_t i;
 	CPTR dvl;
@@ -1579,7 +1579,7 @@ LOCALFUNC tMacErr Sony_OpenB(CPTR p)
 	return mnvm_noErr;
 }
 
-LOCALFUNC tMacErr Sony_OpenC(CPTR p)
+LOCALFUNC MacErr_t Sony_OpenC(CPTR p)
 {
 #if Sony_dolog
 	dbglog_WriteNote("Sony : OpenC");
@@ -1604,7 +1604,7 @@ LOCALFUNC tMacErr Sony_OpenC(CPTR p)
 
 GLOBALPROC ExtnSony_Access(CPTR p)
 {
-	tMacErr result;
+	MacErr_t result;
 
 	switch (get_vm_word(p + ExtnDat_commnd)) {
 		case kCmndVersion:
diff --git a/src/HW/VIDCARD/VIDEMDEV.c b/src/HW/VIDCARD/VIDEMDEV.c
index e0a7d51..f559d58 100644
--- a/src/HW/VIDCARD/VIDEMDEV.c
+++ b/src/HW/VIDCARD/VIDEMDEV.c
@@ -428,7 +428,7 @@ LOCALFUNC uint16_t Vid_GetMode(void)
 	return (UseColorMode && (vMacScreenDepth != 0)) ? 129 : 128;
 }
 
-LOCALFUNC tMacErr Vid_SetMode(uint16_t v)
+LOCALFUNC MacErr_t Vid_SetMode(uint16_t v)
 {
 	if (
 		(vMacScreenDepth == 0)
@@ -518,7 +518,7 @@ LOCALPROC FillScreenWithGrayPattern(void)
 
 GLOBALPROC ExtnVideo_Access(CPTR p)
 {
-	tMacErr result = mnvm_controlErr;
+	MacErr_t result = mnvm_controlErr;
 
 	switch (get_vm_word(p + ExtnDat_commnd)) {
 		case kCmndVersion:
diff --git a/src/UI/COMOSGLU.c b/src/UI/COMOSGLU.c
index 4b4c082..d539d55 100644
--- a/src/UI/COMOSGLU.c
+++ b/src/UI/COMOSGLU.c
@@ -99,9 +99,9 @@ GLOBALPROC PbufDisposeNotify(tPbuf Pbuf_No)
 	PbufAllocatedMask &= ~ ((uint32_t)1 << Pbuf_No);
 }
 
-GLOBALOSGLUFUNC tMacErr CheckPbuf(tPbuf Pbuf_No)
+GLOBALOSGLUFUNC MacErr_t CheckPbuf(tPbuf Pbuf_No)
 {
-	tMacErr result;
+	MacErr_t result;
 
 	if (Pbuf_No >= NumPbufs) {
 		result = mnvm_nsDrvErr;
@@ -114,9 +114,9 @@ GLOBALOSGLUFUNC tMacErr CheckPbuf(tPbuf Pbuf_No)
 	return result;
 }
 
-GLOBALOSGLUFUNC tMacErr PbufGetSize(tPbuf Pbuf_No, uint32_t *Count)
+GLOBALOSGLUFUNC MacErr_t PbufGetSize(tPbuf Pbuf_No, uint32_t *Count)
 {
-	tMacErr result = CheckPbuf(Pbuf_No);
+	MacErr_t result = CheckPbuf(Pbuf_No);
 
 	if (mnvm_noErr == result) {
 		*Count = PbufSize[Pbuf_No];
diff --git a/src/UI/COMOSGLU.h b/src/UI/COMOSGLU.h
index 36ae50d..9f1a073 100644
--- a/src/UI/COMOSGLU.h
+++ b/src/UI/COMOSGLU.h
@@ -90,8 +90,8 @@ GLOBALVAR uint32_t PbufSize[NumPbufs];
 GLOBALFUNC bool FirstFreePbuf(tPbuf *r);
 GLOBALPROC PbufNewNotify(tPbuf Pbuf_No, uint32_t count);
 GLOBALPROC PbufDisposeNotify(tPbuf Pbuf_No);
-GLOBALOSGLUFUNC tMacErr CheckPbuf(tPbuf Pbuf_No);
-GLOBALOSGLUFUNC tMacErr PbufGetSize(tPbuf Pbuf_No, uint32_t *Count);
+GLOBALOSGLUFUNC MacErr_t CheckPbuf(tPbuf Pbuf_No);
+GLOBALOSGLUFUNC MacErr_t PbufGetSize(tPbuf Pbuf_No, uint32_t *Count);
 #endif
 
 GLOBALFUNC bool FirstFreeDisk(tDrive *Drive_No);
diff --git a/src/UI/CONTROLM.h b/src/UI/CONTROLM.h
index 4e471df..81d1b54 100644
--- a/src/UI/CONTROLM.h
+++ b/src/UI/CONTROLM.h
@@ -1136,7 +1136,7 @@ LOCALPROC WarnMsgUnsupportedROM(void)
 }
 #endif
 
-LOCALFUNC tMacErr ROM_IsValid(void)
+LOCALFUNC MacErr_t ROM_IsValid(void)
 {
 #if CheckRomCheckSum
 	uint32_t CheckSum = Calc_Checksum();
diff --git a/src/UI/MACOSX/OSGLUCCO.m b/src/UI/MACOSX/OSGLUCCO.m
index 9685d7f..3a2ece0 100644
--- a/src/UI/MACOSX/OSGLUCCO.m
+++ b/src/UI/MACOSX/OSGLUCCO.m
@@ -445,9 +445,9 @@ LOCALFUNC bool MacRomanFileNameToNSString(tPbuf i,
 #endif
 
 #if IncludeSonyGetName || IncludeHostTextClipExchange
-LOCALFUNC tMacErr NSStringToRomanPbuf(NSString *string, tPbuf *r)
+LOCALFUNC MacErr_t NSStringToRomanPbuf(NSString *string, tPbuf *r)
 {
-	tMacErr v = mnvm_miscErr;
+	MacErr_t v = mnvm_miscErr;
 	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
 #if 0
 	const char *s = [s0
@@ -708,11 +708,11 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	uint32_t NewSony_Count = 0;
 
@@ -735,9 +735,9 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return err; /*& figure out what really to return &*/
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	long v;
 
@@ -831,7 +831,7 @@ LOCALPROC UnlockFile(FILE *refnum)
 }
 #endif
 
-LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
+LOCALFUNC MacErr_t vSonyEject0(tDrive Drive_No, bool deleteit)
 {
 	FILE *refnum = Drives[Drive_No];
 
@@ -864,13 +864,13 @@ LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
 	return mnvm_noErr;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, false);
 }
 
 #if IncludeSonyNew
-GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEjectDelete(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, true);
 }
@@ -888,9 +888,9 @@ LOCALPROC UnInitDrives(void)
 }
 
 #if IncludeSonyGetName
-GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t vSonyGetName(tDrive Drive_No, tPbuf *r)
 {
-	tMacErr v = mnvm_miscErr;
+	MacErr_t v = mnvm_miscErr;
 	NSString *filePath = DriveNames[Drive_No];
 	if (NULL != filePath) {
 		NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
@@ -970,11 +970,11 @@ LOCALFUNC bool Sony_Insert2(char *s)
 	}
 }
 
-LOCALFUNC tMacErr LoadMacRomPath(NSString *RomPath)
+LOCALFUNC MacErr_t LoadMacRomPath(NSString *RomPath)
 {
 	FILE *ROM_File;
 	int File_Size;
-	tMacErr err = mnvm_fnfErr;
+	MacErr_t err = mnvm_fnfErr;
 	const char *path = [RomPath fileSystemRepresentation];
 
 	ROM_File = fopen(path, "rb");
@@ -1100,10 +1100,10 @@ LOCALPROC MakeNewDisk0(uint32_t L, NSString *sPath)
 
 /* --- ROM --- */
 
-LOCALFUNC tMacErr LoadMacRomFrom(NSString *parentPath)
+LOCALFUNC MacErr_t LoadMacRomFrom(NSString *parentPath)
 {
 	NSString *RomPath;
-	tMacErr err = mnvm_fnfErr;
+	MacErr_t err = mnvm_fnfErr;
 
 	if (FindNamedChildFilePath(parentPath, RomFileName, &RomPath)) {
 		err = LoadMacRomPath(RomPath);
@@ -1112,17 +1112,17 @@ LOCALFUNC tMacErr LoadMacRomFrom(NSString *parentPath)
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromAppDir(void)
+LOCALFUNC MacErr_t LoadMacRomFromAppDir(void)
 {
 	return LoadMacRomFrom(DataPath);
 }
 
-LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
+LOCALFUNC MacErr_t LoadMacRomFromPrefDir(void)
 {
 	NSString *PrefsPath;
 	NSString *GryphelPath;
 	NSString *RomsPath;
-	tMacErr err = mnvm_fnfErr;
+	MacErr_t err = mnvm_fnfErr;
 	NSArray *paths = NSSearchPathForDirectoriesInDomains(
 		NSLibraryDirectory, NSUserDomainMask, YES);
 	if ((nil != paths) && ([paths count] > 0))
@@ -1139,11 +1139,11 @@ LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromGlobalDir(void)
+LOCALFUNC MacErr_t LoadMacRomFromGlobalDir(void)
 {
 	NSString *GryphelPath;
 	NSString *RomsPath;
-	tMacErr err = mnvm_fnfErr;
+	MacErr_t err = mnvm_fnfErr;
 	NSArray *paths = NSSearchPathForDirectoriesInDomains(
 		NSApplicationSupportDirectory, NSLocalDomainMask, NO);
 	if ((nil != paths) && ([paths count] > 0))
@@ -1161,7 +1161,7 @@ LOCALFUNC tMacErr LoadMacRomFromGlobalDir(void)
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if (mnvm_fnfErr == (err = LoadMacRomFromAppDir()))
 	if (mnvm_fnfErr == (err = LoadMacRomFromPrefDir()))
@@ -1174,11 +1174,11 @@ LOCALFUNC bool LoadMacRom(void)
 
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
+GLOBALOSGLUFUNC MacErr_t HTCEexport(tPbuf i)
 {
 	void *Buffer;
 	uint32_t L;
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	PbufKillToPtr(&Buffer, &L, i);
 
@@ -1222,9 +1222,9 @@ GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEimport(tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t HTCEimport(tPbuf *r)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
 	NSPasteboard *pasteboard = [NSPasteboard generalPasteboard];
 	NSArray *supportedTypes = [NSArray
diff --git a/src/UI/MACOSX/OSGLUOSX.c b/src/UI/MACOSX/OSGLUOSX.c
index 30d2203..a8e87bc 100644
--- a/src/UI/MACOSX/OSGLUOSX.c
+++ b/src/UI/MACOSX/OSGLUOSX.c
@@ -642,11 +642,11 @@ LOCALPROC PStrFromChar(ps3p r, char x)
 
 #define CheckSavetMacErr(result) (mnvm_noErr == (err = (result)))
 	/*
-		where 'err' is a variable of type tMacErr in the function
+		where 'err' is a variable of type MacErr_t in the function
 		this is used in
 	*/
 
-#define To_tMacErr(result) ((tMacErr)(uint16_t)(result))
+#define To_tMacErr(result) ((MacErr_t)(uint16_t)(result))
 
 #define CheckSaveMacErr(result) (CheckSavetMacErr(To_tMacErr(result)))
 
@@ -674,11 +674,11 @@ LOCALPROC UniCharStrFromSubstCStr(int *L, UniChar *x, char *s)
 
 #define NotAfileRef (-1)
 
-LOCALFUNC tMacErr MakeFSRefUniChar(FSRef *ParentRef,
+LOCALFUNC MacErr_t MakeFSRefUniChar(FSRef *ParentRef,
 	UniCharCount fileNameLength, const UniChar *fileName,
 	bool *isFolder, FSRef *ChildRef)
 {
-	tMacErr err;
+	MacErr_t err;
 	Boolean isFolder0;
 	Boolean isAlias;
 
@@ -694,7 +694,7 @@ LOCALFUNC tMacErr MakeFSRefUniChar(FSRef *ParentRef,
 	return err;
 }
 
-LOCALFUNC tMacErr MakeFSRefC(FSRef *ParentRef, char *fileName,
+LOCALFUNC MacErr_t MakeFSRefC(FSRef *ParentRef, char *fileName,
 	bool *isFolder, FSRef *ChildRef)
 {
 	int L;
@@ -706,10 +706,10 @@ LOCALFUNC tMacErr MakeFSRefC(FSRef *ParentRef, char *fileName,
 }
 
 #if UseActvFile
-LOCALFUNC tMacErr OpenNamedFileInFolderRef(FSRef *ParentRef,
+LOCALFUNC MacErr_t OpenNamedFileInFolderRef(FSRef *ParentRef,
 	char *fileName, short *refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 	bool isFolder;
 	FSRef ChildRef;
 	HFSUniStr255 forkName;
@@ -728,10 +728,10 @@ LOCALFUNC tMacErr OpenNamedFileInFolderRef(FSRef *ParentRef,
 #endif
 
 #if dbglog_HAVE || UseActvFile
-LOCALFUNC tMacErr OpenWriteNamedFileInFolderRef(FSRef *ParentRef,
+LOCALFUNC MacErr_t OpenWriteNamedFileInFolderRef(FSRef *ParentRef,
 	char *fileName, short *refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 	bool isFolder;
 	FSRef ChildRef;
 	HFSUniStr255 forkName;
@@ -757,10 +757,10 @@ LOCALFUNC tMacErr OpenWriteNamedFileInFolderRef(FSRef *ParentRef,
 }
 #endif
 
-LOCALFUNC tMacErr FindNamedChildRef(FSRef *ParentRef,
+LOCALFUNC MacErr_t FindNamedChildRef(FSRef *ParentRef,
 	char *ChildName, FSRef *ChildRef)
 {
-	tMacErr err;
+	MacErr_t err;
 	bool isFolder;
 
 	if (CheckSavetMacErr(MakeFSRefC(ParentRef, ChildName,
@@ -775,10 +775,10 @@ LOCALFUNC tMacErr FindNamedChildRef(FSRef *ParentRef,
 }
 
 #if UseActvFile || (IncludeSonyNew && ! SaveDialogEnable)
-LOCALFUNC tMacErr FindOrMakeNamedChildRef(FSRef *ParentRef,
+LOCALFUNC MacErr_t FindOrMakeNamedChildRef(FSRef *ParentRef,
 	char *ChildName, FSRef *ChildRef)
 {
-	tMacErr err;
+	MacErr_t err;
 	bool isFolder;
 	int L;
 	UniChar x[ClStrMaxLength];
@@ -857,7 +857,7 @@ LOCALVAR SInt16 dbglog_File = NotAfileRef;
 
 LOCALFUNC bool dbglog_open0(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	err = OpenWriteNamedFileInFolderRef(&DatDirRef,
 		"dbglog.txt", &dbglog_File);
@@ -974,12 +974,12 @@ LOCALFUNC bool CheckDateTime(void)
 
 LOCALVAR SInt16 Drives[NumDrives]; /* open disk image files */
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
 	ByteCount actualCount;
-	tMacErr result;
+	MacErr_t result;
 
 	if (IsWrite) {
 		result = To_tMacErr(FSWriteFork(
@@ -1006,16 +1006,16 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return result;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
 	SInt64 forkSize;
-	tMacErr err = To_tMacErr(
+	MacErr_t err = To_tMacErr(
 		FSGetForkSize(Drives[Drive_No], &forkSize));
 	*Sony_Count = forkSize;
 	return err;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	SInt16 refnum = Drives[Drive_No];
 	Drives[Drive_No] = NotAfileRef;
@@ -1028,11 +1028,11 @@ GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
 }
 
 #if IncludeSonyNew
-GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEjectDelete(tDrive Drive_No)
 {
 	FSRef ref;
-	tMacErr err0;
-	tMacErr err;
+	MacErr_t err0;
+	MacErr_t err;
 
 	err0 = To_tMacErr(FSGetForkCBInfo(Drives[Drive_No], 0,
 		NULL /* iterator */,
@@ -1053,12 +1053,12 @@ GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
 #endif
 
 #if IncludeSonyGetName
-GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t vSonyGetName(tDrive Drive_No, tPbuf *r)
 {
 	FSRef ref;
 	HFSUniStr255 outName;
 	CFStringRef DiskName;
-	tMacErr err;
+	MacErr_t err;
 
 	if (CheckSaveMacErr(FSGetForkCBInfo(Drives[Drive_No], 0,
 		NULL /* iterator */,
@@ -1105,9 +1105,9 @@ GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
+GLOBALOSGLUFUNC MacErr_t HTCEexport(tPbuf i)
 {
-	tMacErr err;
+	MacErr_t err;
 	ScrapRef scrapRef;
 
 	if (CheckSaveMacErr(ClearCurrentScrap()))
@@ -1129,9 +1129,9 @@ GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEimport(tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t HTCEimport(tPbuf *r)
 {
-	tMacErr err;
+	MacErr_t err;
 	ScrapRef scrap;
 	ScrapFlavorFlags flavorFlags;
 	Size byteCount;
@@ -2889,7 +2889,7 @@ LOCALPROC UnInitDrives(void)
 	}
 }
 
-LOCALFUNC tMacErr Sony_Insert0(SInt16 refnum, bool locked)
+LOCALFUNC MacErr_t Sony_Insert0(SInt16 refnum, bool locked)
 {
 	tDrive Drive_No;
 
@@ -2903,7 +2903,7 @@ LOCALFUNC tMacErr Sony_Insert0(SInt16 refnum, bool locked)
 	}
 }
 
-LOCALPROC ReportStandardOpenDiskError(tMacErr err)
+LOCALPROC ReportStandardOpenDiskError(MacErr_t err)
 {
 	if (mnvm_noErr != err) {
 		if (mnvm_tmfoErr == err) {
@@ -2918,9 +2918,9 @@ LOCALPROC ReportStandardOpenDiskError(tMacErr err)
 	}
 }
 
-LOCALFUNC tMacErr InsertADiskFromFSRef(FSRef *theRef)
+LOCALFUNC MacErr_t InsertADiskFromFSRef(FSRef *theRef)
 {
-	tMacErr err;
+	MacErr_t err;
 	HFSUniStr255 forkName;
 	SInt16 refnum;
 	bool locked = false;
@@ -2947,9 +2947,9 @@ LOCALFUNC tMacErr InsertADiskFromFSRef(FSRef *theRef)
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromRefNum(SInt16 refnum)
+LOCALFUNC MacErr_t LoadMacRomFromRefNum(SInt16 refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 	ByteCount actualCount;
 
 	if (mnvm_noErr != (err = To_tMacErr(
@@ -2969,9 +2969,9 @@ LOCALFUNC tMacErr LoadMacRomFromRefNum(SInt16 refnum)
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromFSRef(FSRef *theRef)
+LOCALFUNC MacErr_t LoadMacRomFromFSRef(FSRef *theRef)
 {
-	tMacErr err;
+	MacErr_t err;
 	HFSUniStr255 forkName;
 	SInt16 refnum;
 
@@ -2989,9 +2989,9 @@ LOCALFUNC tMacErr LoadMacRomFromFSRef(FSRef *theRef)
 	return err;
 }
 
-LOCALFUNC tMacErr InsertADiskFromFSRef1(FSRef *theRef)
+LOCALFUNC MacErr_t InsertADiskFromFSRef1(FSRef *theRef)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if (! ROM_loaded) {
 		err = LoadMacRomFromFSRef(theRef);
@@ -3002,9 +3002,9 @@ LOCALFUNC tMacErr InsertADiskFromFSRef1(FSRef *theRef)
 	return err;
 }
 
-LOCALFUNC tMacErr InsertDisksFromDocList(AEDescList *docList)
+LOCALFUNC MacErr_t InsertDisksFromDocList(AEDescList *docList)
 {
-	tMacErr err = mnvm_noErr;
+	MacErr_t err = mnvm_noErr;
 	long itemsInList;
 	long index;
 	AEKeyword keyword;
@@ -3030,10 +3030,10 @@ label_fail:
 	return err;
 }
 
-LOCALFUNC tMacErr InsertADiskFromNameEtc(FSRef *ParentRef,
+LOCALFUNC MacErr_t InsertADiskFromNameEtc(FSRef *ParentRef,
 	char *fileName)
 {
-	tMacErr err;
+	MacErr_t err;
 	bool isFolder;
 	FSRef ChildRef;
 
@@ -3053,10 +3053,10 @@ LOCALFUNC tMacErr InsertADiskFromNameEtc(FSRef *ParentRef,
 }
 
 #if IncludeSonyNew
-LOCALFUNC tMacErr WriteZero(SInt16 refnum, uint32_t L)
+LOCALFUNC MacErr_t WriteZero(SInt16 refnum, uint32_t L)
 {
 #define ZeroBufferSize 2048
-	tMacErr err = mnvm_noErr;
+	MacErr_t err = mnvm_noErr;
 	uint32_t i;
 	uint8_t buffer[ZeroBufferSize];
 	ByteCount actualCount;
@@ -3085,10 +3085,10 @@ label_fail:
 #endif
 
 #if IncludeSonyNew
-LOCALFUNC tMacErr CreateFileCFStringRef(FSRef *saveFileParent,
+LOCALFUNC MacErr_t CreateFileCFStringRef(FSRef *saveFileParent,
 	CFStringRef saveFileName, FSRef *NewRef)
 {
-	tMacErr err;
+	MacErr_t err;
 	UniChar buffer[255];
 
 	CFIndex len = CFStringGetLength(saveFileName);
@@ -3111,10 +3111,10 @@ LOCALFUNC tMacErr CreateFileCFStringRef(FSRef *saveFileParent,
 #endif
 
 #if IncludeSonyNew
-LOCALFUNC tMacErr MakeNewDisk0(FSRef *saveFileParent,
+LOCALFUNC MacErr_t MakeNewDisk0(FSRef *saveFileParent,
 	CFStringRef saveFileName, uint32_t L)
 {
-	tMacErr err;
+	MacErr_t err;
 	FSRef NewRef;
 	HFSUniStr255 forkName;
 	SInt16 refnum;
@@ -3331,10 +3331,10 @@ LOCALPROC MakeNewDisk(uint32_t L, CFStringRef NewDiskName)
 }
 #endif
 
-LOCALFUNC tMacErr LoadMacRomFromNameFolder(FSRef *ParentRef,
+LOCALFUNC MacErr_t LoadMacRomFromNameFolder(FSRef *ParentRef,
 	char *fileName)
 {
-	tMacErr err;
+	MacErr_t err;
 	bool isFolder;
 	FSRef ChildRef;
 
@@ -3348,9 +3348,9 @@ LOCALFUNC tMacErr LoadMacRomFromNameFolder(FSRef *ParentRef,
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
+LOCALFUNC MacErr_t LoadMacRomFromPrefDir(void)
 {
-	tMacErr err;
+	MacErr_t err;
 	FSRef PrefRef;
 	FSRef GryphelRef;
 	FSRef ROMsRef;
@@ -3372,7 +3372,7 @@ LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if (mnvm_fnfErr == (err =
 		LoadMacRomFromNameFolder(&DatDirRef, RomFileName)))
@@ -3386,7 +3386,7 @@ LOCALFUNC bool LoadMacRom(void)
 
 LOCALFUNC bool Sony_InsertIth(int i)
 {
-	tMacErr err = mnvm_noErr;
+	MacErr_t err = mnvm_noErr;
 
 	if ((i > 9) || ! FirstFreeDisk(nullpr)) {
 		return false;
@@ -3423,9 +3423,9 @@ LOCALFUNC bool LoadInitialImages(void)
 
 #define ActvCodeFileName "act_1"
 
-LOCALFUNC tMacErr OpenActvCodeFile(SInt16 *refnum)
+LOCALFUNC MacErr_t OpenActvCodeFile(SInt16 *refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 	FSRef PrefRef;
 	FSRef GryphelRef;
 	FSRef ActRef;
@@ -3445,9 +3445,9 @@ LOCALFUNC tMacErr OpenActvCodeFile(SInt16 *refnum)
 	return err;
 }
 
-LOCALFUNC tMacErr ActvCodeFileLoad(uint8_t * p)
+LOCALFUNC MacErr_t ActvCodeFileLoad(uint8_t * p)
 {
-	tMacErr err;
+	MacErr_t err;
 	SInt16 refnum;
 
 	if (CheckSavetMacErr(OpenActvCodeFile(&refnum))) {
@@ -3460,9 +3460,9 @@ LOCALFUNC tMacErr ActvCodeFileLoad(uint8_t * p)
 	return err;
 }
 
-LOCALFUNC tMacErr ActvCodeFileSave(uint8_t * p)
+LOCALFUNC MacErr_t ActvCodeFileSave(uint8_t * p)
 {
-	tMacErr err;
+	MacErr_t err;
 	SInt16 refnum;
 	FSRef PrefRef;
 	FSRef GryphelRef;
@@ -3683,9 +3683,9 @@ static pascal OSErr GlobalTrackingHandler(DragTrackingMessage message,
 	return noErr;
 }
 
-LOCALFUNC tMacErr InsertADiskOrAliasFromFSRef(FSRef *theRef)
+LOCALFUNC MacErr_t InsertADiskOrAliasFromFSRef(FSRef *theRef)
 {
-	tMacErr err;
+	MacErr_t err;
 	Boolean isFolder;
 	Boolean isAlias;
 
@@ -3698,9 +3698,9 @@ LOCALFUNC tMacErr InsertADiskOrAliasFromFSRef(FSRef *theRef)
 	return err;
 }
 
-LOCALFUNC tMacErr InsertADiskOrAliasFromSpec(FSSpec *spec)
+LOCALFUNC MacErr_t InsertADiskOrAliasFromSpec(FSSpec *spec)
 {
-	tMacErr err;
+	MacErr_t err;
 	FSRef newRef;
 
 	if (CheckSaveMacErr(FSpMakeFSRef(spec, &newRef)))
diff --git a/src/UI/NDS/OSGLUNDS.c b/src/UI/NDS/OSGLUNDS.c
index 28dc905..3452cfc 100644
--- a/src/UI/NDS/OSGLUNDS.c
+++ b/src/UI/NDS/OSGLUNDS.c
@@ -164,11 +164,11 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	uint32_t NewSony_Count = 0;
 
@@ -191,9 +191,9 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return err; /*& figure out what really to return &*/
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	long v;
 
@@ -208,7 +208,7 @@ GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 	return err; /*& figure out what really to return &*/
 }
 
-LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
+LOCALFUNC MacErr_t vSonyEject0(tDrive Drive_No, bool deleteit)
 {
 	FILE *refnum = Drives[Drive_No];
 
@@ -233,13 +233,13 @@ LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
 	return mnvm_noErr;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, false);
 }
 
 #if IncludeSonyNew
-GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEjectDelete(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, true);
 }
@@ -257,7 +257,7 @@ LOCALPROC UnInitDrives(void)
 }
 
 #if IncludeSonyGetName
-GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t vSonyGetName(tDrive Drive_No, tPbuf *r)
 {
 	char *drivepath = DriveNames[Drive_No];
 	if (NULL == drivepath) {
@@ -421,9 +421,9 @@ LOCALPROC MakeNewDiskAtDefault(uint32_t L)
 
 /* --- ROM --- */
 
-LOCALFUNC tMacErr LoadMacRomFrom(char *path)
+LOCALFUNC MacErr_t LoadMacRomFrom(char *path)
 {
-	tMacErr err;
+	MacErr_t err;
 	FILE *ROM_File;
 	int File_Size;
 
@@ -453,7 +453,7 @@ LOCALFUNC tMacErr LoadMacRomFrom(char *path)
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if (mnvm_fnfErr == (err = LoadMacRomFrom(RomFileName)))
 	{
diff --git a/src/UI/OLDMAC/OSGLUMAC.c b/src/UI/OLDMAC/OSGLUMAC.c
index a267774..a979912 100644
--- a/src/UI/OLDMAC/OSGLUMAC.c
+++ b/src/UI/OLDMAC/OSGLUMAC.c
@@ -378,11 +378,11 @@ LOCALFUNC bool InitMacManagers(void)
 
 #define CheckSavetMacErr(result) (mnvm_noErr == (err = (result)))
 	/*
-		where 'err' is a variable of type tMacErr in the function
+		where 'err' is a variable of type MacErr_t in the function
 		this is used in
 	*/
 
-#define To_tMacErr(result) ((tMacErr)(uint16_t)(result))
+#define To_tMacErr(result) ((MacErr_t)(uint16_t)(result))
 
 #define CheckSaveMacErr(result) (CheckSavetMacErr(To_tMacErr(result)))
 
@@ -399,10 +399,10 @@ struct Dir_R {
 };
 typedef struct Dir_R Dir_R;
 
-LOCALFUNC tMacErr OpenNamedFileInFolder(Dir_R *d,
+LOCALFUNC MacErr_t OpenNamedFileInFolder(Dir_R *d,
 	ps3p fileName, short *refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 
 #if HaveCPUfamM68K
 	if (! HaveFSSpecCallsAvail()) {
@@ -432,7 +432,7 @@ LOCALFUNC tMacErr OpenNamedFileInFolder(Dir_R *d,
 #if dbglog_HAVE
 
 #define Support64kROM 0
-#define tErr tMacErr
+#define tErr MacErr_t
 
 typedef unsigned char * Ptr;
 
@@ -695,7 +695,7 @@ LOCALVAR tErr dbglog_err = noErr;
 
 LOCALFUNC bool dbglog_open0(void)
 {
-	tMacErr err;
+	MacErr_t err;
 	Dir_R d;
 
 	if (noErr == (err = HGetDir_v2(&d))) {
@@ -796,7 +796,7 @@ LOCALPROC PStrFromHandle(ps3p r, Handle h, uint32_t MaxL)
 	BlockMove(*h, (Ptr)r, L);
 }
 
-LOCALFUNC tMacErr PStrToHand(ps3p s, Handle *r)
+LOCALFUNC MacErr_t PStrToHand(ps3p s, Handle *r)
 {
 	return To_tMacErr(PtrToHand((Ptr)(s + 1), r, s[0]));
 }
@@ -2584,10 +2584,10 @@ LOCALVAR Handle PbufDat[NumPbufs];
 #endif
 
 #if IncludePbufs
-LOCALFUNC tMacErr PbufNewFromHandle(Handle h, uint32_t count, tPbuf *r)
+LOCALFUNC MacErr_t PbufNewFromHandle(Handle h, uint32_t count, tPbuf *r)
 {
 	tPbuf i;
-	tMacErr err;
+	MacErr_t err;
 
 	if (! FirstFreePbuf(&i)) {
 		DisposeHandle(h);
@@ -2604,10 +2604,10 @@ LOCALFUNC tMacErr PbufNewFromHandle(Handle h, uint32_t count, tPbuf *r)
 #endif
 
 #if IncludePbufs
-GLOBALOSGLUFUNC tMacErr PbufNew(uint32_t count, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t PbufNew(uint32_t count, tPbuf *r)
 {
 	Handle h;
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	h = NewHandleClear(count);
 	if (h != NULL) {
@@ -2690,7 +2690,7 @@ GLOBALOSGLUPROC PbufTransfer(uint8_t * Buffer,
 /* --- clipboard --- */
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
+GLOBALOSGLUFUNC MacErr_t HTCEexport(tPbuf i)
 {
 	/*
 		PBuf i is an array of macintosh
@@ -2719,12 +2719,12 @@ GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
 
 	PbufDispose(i);
 
-	return (tMacErr)err;
+	return (MacErr_t)err;
 }
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEimport(tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t HTCEimport(tPbuf *r)
 {
 	/*
 		Import the native clipboard as text,
@@ -2755,7 +2755,7 @@ GLOBALOSGLUFUNC tMacErr HTCEimport(tPbuf *r)
 		}
 	}
 
-	return (tMacErr)err;
+	return (MacErr_t)err;
 }
 #endif
 
@@ -2782,7 +2782,7 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
@@ -2791,11 +2791,11 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 		Macintosh style error code, but -1
 		will do) on failure.
 	*/
-	tMacErr result;
+	MacErr_t result;
 	uint32_t NewSony_Count = Sony_Count;
 
 	result =
-		(tMacErr)SetFPos(Drives[Drive_No], fsFromStart, Sony_Start);
+		(MacErr_t)SetFPos(Drives[Drive_No], fsFromStart, Sony_Start);
 	if (mnvm_noErr == result) {
 		if (IsWrite) {
 			/*
@@ -2803,7 +2803,7 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 				number Drive_No, starting at offset Sony_Start.
 			*/
 
-			result = (tMacErr)FSWrite(Drives[Drive_No],
+			result = (MacErr_t)FSWrite(Drives[Drive_No],
 				(long *)&NewSony_Count, Buffer);
 		} else {
 			/*
@@ -2811,7 +2811,7 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 				number Drive_No, starting at offset Sony_Start.
 			*/
 
-			result = (tMacErr)FSRead(Drives[Drive_No],
+			result = (MacErr_t)FSRead(Drives[Drive_No],
 				(long *)&NewSony_Count, Buffer);
 		}
 	}
@@ -2823,7 +2823,7 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return result;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
 	/*
 		set Sony_Count to the size of disk image number Drive_No.
@@ -2862,7 +2862,7 @@ LOCALFUNC OSErr vSonyEject0(tDrive Drive_No)
 	return FSClose(refnum);
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	OSErr result;
 	short vRefNum;
@@ -2880,11 +2880,11 @@ GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
 		result = vSonyEject0(Drive_No);
 	}
 
-	return (tMacErr)result;
+	return (MacErr_t)result;
 }
 
 #if IncludeSonyNew
-GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEjectDelete(tDrive Drive_No)
 {
 	OSErr result;
 	Str255 s;
@@ -2931,7 +2931,7 @@ GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
 		(void) vSonyEject0(Drive_No);
 	}
 
-	return (tMacErr)result;
+	return (MacErr_t)result;
 }
 #endif
 
@@ -2947,11 +2947,11 @@ LOCALPROC UnInitDrives(void)
 }
 
 #if IncludeSonyGetName
-GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t vSonyGetName(tDrive Drive_No, tPbuf *r)
 {
 	FCBPBRec b;
 	Str255 s;
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 #if HaveCPUfamM68K
 	if (! HaveFSSpecCallsAvail()) {
@@ -2983,7 +2983,7 @@ GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
 }
 #endif
 
-LOCALFUNC tMacErr Sony_Insert0(short refnum, bool locked, ps3p s)
+LOCALFUNC MacErr_t Sony_Insert0(short refnum, bool locked, ps3p s)
 {
 	/*
 		Given reference to open file, mount it as
@@ -3017,7 +3017,7 @@ LOCALFUNC tMacErr Sony_Insert0(short refnum, bool locked, ps3p s)
 	}
 }
 
-LOCALPROC ReportStandardOpenDiskError(tMacErr err)
+LOCALPROC ReportStandardOpenDiskError(MacErr_t err)
 {
 	if (mnvm_noErr != err) {
 		if (mnvm_tmfoErr == err) {
@@ -3032,10 +3032,10 @@ LOCALPROC ReportStandardOpenDiskError(tMacErr err)
 	}
 }
 
-LOCALFUNC tMacErr InsertADiskFromFileRef(FSSpec *spec)
+LOCALFUNC MacErr_t InsertADiskFromFileRef(FSSpec *spec)
 {
 	short refnum;
-	tMacErr err;
+	MacErr_t err;
 	bool locked = false;
 
 	err = To_tMacErr(FSpOpenDF(spec, fsRdWrPerm, &refnum));
@@ -3057,11 +3057,11 @@ LOCALFUNC tMacErr InsertADiskFromFileRef(FSSpec *spec)
 }
 
 #if HaveCPUfamM68K
-LOCALFUNC tMacErr InsertADiskFromNamevRef(ConstStr255Param fileName,
+LOCALFUNC MacErr_t InsertADiskFromNamevRef(ConstStr255Param fileName,
 	short vRefNum)
 {
 	ParamBlockRec R;
-	tMacErr err;
+	MacErr_t err;
 	bool locked = false;
 
 	R.ioParam.ioCompletion = NULL;
@@ -3090,12 +3090,12 @@ LOCALFUNC tMacErr InsertADiskFromNamevRef(ConstStr255Param fileName,
 }
 #endif
 
-LOCALFUNC tMacErr LoadMacRomFromRefNum(short refnum)
+LOCALFUNC MacErr_t LoadMacRomFromRefNum(short refnum)
 {
 	/*
 		load the ROM image file into ptr ROM
 	*/
-	tMacErr err;
+	MacErr_t err;
 	long count = kROM_Size;
 
 	if (mnvm_noErr != (err = To_tMacErr(
@@ -3114,9 +3114,9 @@ LOCALFUNC tMacErr LoadMacRomFromRefNum(short refnum)
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromFSSpec(FSSpec *spec)
+LOCALFUNC MacErr_t LoadMacRomFromFSSpec(FSSpec *spec)
 {
-	tMacErr err;
+	MacErr_t err;
 	short refnum;
 
 	if (mnvm_noErr == (err =
@@ -3130,10 +3130,10 @@ LOCALFUNC tMacErr LoadMacRomFromFSSpec(FSSpec *spec)
 }
 
 #if HaveCPUfamM68K
-LOCALFUNC tMacErr LoadMacRomFromNamevRef(ConstStr255Param fileName,
+LOCALFUNC MacErr_t LoadMacRomFromNamevRef(ConstStr255Param fileName,
 	short vRefNum)
 {
-	tMacErr err;
+	MacErr_t err;
 	ParamBlockRec R;
 
 	R.ioParam.ioCompletion = NULL;
@@ -3152,10 +3152,10 @@ LOCALFUNC tMacErr LoadMacRomFromNamevRef(ConstStr255Param fileName,
 #endif
 
 #if HaveCPUfamM68K
-LOCALFUNC tMacErr InsertADiskFromNamevRef1(ConstStr255Param fileName,
+LOCALFUNC MacErr_t InsertADiskFromNamevRef1(ConstStr255Param fileName,
 	short vRefNum)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if (! ROM_loaded) {
 		err = LoadMacRomFromNamevRef(fileName, vRefNum);
@@ -3167,12 +3167,12 @@ LOCALFUNC tMacErr InsertADiskFromNamevRef1(ConstStr255Param fileName,
 }
 #endif
 
-LOCALFUNC tMacErr InsertADiskOrAliasFromSpec(FSSpec *spec,
+LOCALFUNC MacErr_t InsertADiskOrAliasFromSpec(FSSpec *spec,
 	bool MaybeROM, bool MaybeAlias)
 {
 	Boolean isFolder;
 	Boolean isAlias;
-	tMacErr err;
+	MacErr_t err;
 
 	if ((! MaybeAlias)
 		|| CheckSaveMacErr(ResolveAliasFile(spec, true,
@@ -3188,9 +3188,9 @@ LOCALFUNC tMacErr InsertADiskOrAliasFromSpec(FSSpec *spec,
 	return err;
 }
 
-LOCALFUNC tMacErr InsertDisksFromDocList(AEDescList *docList)
+LOCALFUNC MacErr_t InsertDisksFromDocList(AEDescList *docList)
 {
-	tMacErr err = mnvm_noErr;
+	MacErr_t err = mnvm_noErr;
 	long itemsInList;
 	long index;
 	AEKeyword keyword;
@@ -3217,10 +3217,10 @@ label_fail:
 	return err;
 }
 
-LOCALFUNC tMacErr InsertADiskFromNameEtc(Dir_R *d,
+LOCALFUNC MacErr_t InsertADiskFromNameEtc(Dir_R *d,
 	ConstStr255Param fileName)
 {
-	tMacErr err;
+	MacErr_t err;
 
 #if HaveCPUfamM68K
 	if (! HaveFSSpecCallsAvail()) {
@@ -3468,9 +3468,9 @@ LOCALFUNC bool InitApplInfo(void)
 	return false;
 }
 
-LOCALFUNC tMacErr DirFromWD_v2(short VRefNum, Dir_R *d)
+LOCALFUNC MacErr_t DirFromWD_v2(short VRefNum, Dir_R *d)
 {
-	tMacErr err;
+	MacErr_t err;
 	Str63 s;
 	WDPBRec pb;
 
@@ -3497,9 +3497,9 @@ LOCALFUNC tMacErr DirFromWD_v2(short VRefNum, Dir_R *d)
 	return err;
 }
 
-LOCALFUNC tMacErr FindPrefFolder(Dir_R *d)
+LOCALFUNC MacErr_t FindPrefFolder(Dir_R *d)
 {
-	tMacErr err;
+	MacErr_t err;
 	long reply;
 
 	if (HaveGestaltAvail()
@@ -3538,10 +3538,10 @@ LOCALPROC PStrCopy(ps3p r, ps3p s)
 	MoveBytes((anyp)s, (anyp)r, PStrToTotSize(s));
 }
 
-LOCALFUNC tMacErr FindNamedChildDir_v2(Dir_R *src_d, StringPtr s,
+LOCALFUNC MacErr_t FindNamedChildDir_v2(Dir_R *src_d, StringPtr s,
 	Dir_R *dst_d)
 {
-	tMacErr err;
+	MacErr_t err;
 	Str255 NameBuffer;
 	CInfoPBRec cPB;
 
@@ -3566,10 +3566,10 @@ LOCALFUNC tMacErr FindNamedChildDir_v2(Dir_R *src_d, StringPtr s,
 	return err;
 }
 
-LOCALFUNC tMacErr ResolveAliasDir_v2(Dir_R *src_d, StringPtr s,
+LOCALFUNC MacErr_t ResolveAliasDir_v2(Dir_R *src_d, StringPtr s,
 	Dir_R *dst_d)
 {
-	tMacErr err;
+	MacErr_t err;
 	FSSpec spec;
 	Boolean isFolder;
 	Boolean isAlias;
@@ -3593,10 +3593,10 @@ LOCALFUNC tMacErr ResolveAliasDir_v2(Dir_R *src_d, StringPtr s,
 	return err;
 }
 
-LOCALFUNC tMacErr ResolveNamedChildDir_v2(Dir_R *src_d, StringPtr s,
+LOCALFUNC MacErr_t ResolveNamedChildDir_v2(Dir_R *src_d, StringPtr s,
 	Dir_R *dst_d)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	err = FindNamedChildDir_v2(src_d, s, dst_d);
 	if (mnvm_dirNFErr == err) {
@@ -3608,7 +3608,7 @@ LOCALFUNC tMacErr ResolveNamedChildDir_v2(Dir_R *src_d, StringPtr s,
 	return err;
 }
 
-LOCALFUNC tMacErr OpenNamedFileInFolderCStr(Dir_R *d,
+LOCALFUNC MacErr_t OpenNamedFileInFolderCStr(Dir_R *d,
 	char *s, short *refnum)
 {
 	Str255 fileName;
@@ -3617,7 +3617,7 @@ LOCALFUNC tMacErr OpenNamedFileInFolderCStr(Dir_R *d,
 	return OpenNamedFileInFolder(d, fileName, refnum);
 }
 
-LOCALFUNC tMacErr ResolveNamedChildDirCStr(Dir_R *src_d,
+LOCALFUNC MacErr_t ResolveNamedChildDirCStr(Dir_R *src_d,
 	char *s, Dir_R *dst_d)
 {
 	Str255 fileName;
@@ -3626,10 +3626,10 @@ LOCALFUNC tMacErr ResolveNamedChildDirCStr(Dir_R *src_d,
 	return ResolveNamedChildDir_v2(src_d, fileName, dst_d);
 }
 
-LOCALFUNC tMacErr LoadMacRomFromNameFolder(Dir_R *d,
+LOCALFUNC MacErr_t LoadMacRomFromNameFolder(Dir_R *d,
 	char *s)
 {
-	tMacErr err;
+	MacErr_t err;
 	short refnum;
 
 	if (mnvm_noErr == (err =
@@ -3642,9 +3642,9 @@ LOCALFUNC tMacErr LoadMacRomFromNameFolder(Dir_R *d,
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
+LOCALFUNC MacErr_t LoadMacRomFromPrefDir(void)
 {
-	tMacErr err;
+	MacErr_t err;
 	Dir_R PrefRef;
 	Dir_R GryphelRef;
 	Dir_R ROMsRef;
@@ -3665,7 +3665,7 @@ LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if (mnvm_fnfErr == (err =
 		LoadMacRomFromNameFolder(&DatDir, RomFileName)))
@@ -3683,7 +3683,7 @@ LOCALFUNC bool Sony_InsertIth(int i)
 		return false;
 	} else {
 		Str255 s;
-		tMacErr err = mnvm_noErr;
+		MacErr_t err = mnvm_noErr;
 
 		PStrFromCStr(s, "disk?.dsk");
 
@@ -3711,10 +3711,10 @@ LOCALFUNC bool LoadInitialImages(void)
 }
 
 #if IncludeSonyNew
-LOCALFUNC tMacErr WriteZero(SInt16 refnum, uint32_t L)
+LOCALFUNC MacErr_t WriteZero(SInt16 refnum, uint32_t L)
 {
 #define ZeroBufferSize 2048
-	tMacErr err;
+	MacErr_t err;
 	uint32_t i;
 	uint8_t buffer[ZeroBufferSize];
 
@@ -3743,7 +3743,7 @@ LOCALPROC MakeNewDiskFromNamevRef(ps3p Name, short vRefNum,
 	uint32_t L)
 {
 	short refNum;
-	tMacErr err;
+	MacErr_t err;
 
 	err = To_tMacErr(Create(Name, vRefNum, '????', '????'));
 	if (mnvm_dupFNErr == err) {
@@ -3776,7 +3776,7 @@ LOCALPROC MakeNewDiskFromSpec(FSSpec *NewFileSpec,
 	uint32_t L)
 {
 	short refNum;
-	tMacErr err;
+	MacErr_t err;
 
 	err = To_tMacErr(FSpCreate(NewFileSpec,
 		'????', '????', smSystemScript));
@@ -3810,10 +3810,10 @@ LOCALPROC MakeNewDiskFromSpec(FSSpec *NewFileSpec,
 #endif
 
 #if UseActvFile || (IncludeSonyNew && ! SaveDialogEnable)
-LOCALFUNC tMacErr MakeNamedDir_v2(Dir_R *d, StringPtr s,
+LOCALFUNC MacErr_t MakeNamedDir_v2(Dir_R *d, StringPtr s,
 	Dir_R *new_d)
 {
-	tMacErr err;
+	MacErr_t err;
 	HParamBlockRec r;
 
 	r.fileParam.ioCompletion = NULL;
@@ -3831,10 +3831,10 @@ LOCALFUNC tMacErr MakeNamedDir_v2(Dir_R *d, StringPtr s,
 #endif
 
 #if UseActvFile || (IncludeSonyNew && ! SaveDialogEnable)
-LOCALFUNC tMacErr FindOrMakeMakeNamedDir_v2(Dir_R *new_d,
+LOCALFUNC MacErr_t FindOrMakeMakeNamedDir_v2(Dir_R *new_d,
 	Dir_R *d, StringPtr s)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	err = ResolveNamedChildDir_v2(d, s, new_d);
 	if (mnvm_fnfErr == err) {
@@ -3846,7 +3846,7 @@ LOCALFUNC tMacErr FindOrMakeMakeNamedDir_v2(Dir_R *new_d,
 #endif
 
 #if UseActvFile || (IncludeSonyNew && ! SaveDialogEnable)
-LOCALFUNC tMacErr FindOrMakeChildDirCStr(Dir_R *new_d,
+LOCALFUNC MacErr_t FindOrMakeChildDirCStr(Dir_R *new_d,
 	Dir_R *d, char *name)
 {
 	Str255 s;
@@ -3950,7 +3950,7 @@ LOCALPROC MakeNewDisk(uint32_t L, Handle NewDiskName)
 		}
 	}
 #else /* SaveDialogEnable */
-	tMacErr err;
+	MacErr_t err;
 	Str255 Title;
 	Dir_R OutDir;
 	FSSpec spec;
@@ -3986,9 +3986,9 @@ LOCALPROC MakeNewDisk(uint32_t L, Handle NewDiskName)
 
 #if UseActvFile
 
-LOCALFUNC tMacErr CreateFile_v2(Dir_R *d, StringPtr s)
+LOCALFUNC MacErr_t CreateFile_v2(Dir_R *d, StringPtr s)
 {
-	tMacErr err;
+	MacErr_t err;
 	HParamBlockRec r;
 
 	r.fileParam.ioFlVersNum = 0;
@@ -4015,9 +4015,9 @@ LOCALFUNC tMacErr CreateFile_v2(Dir_R *d, StringPtr s)
 	return err;
 }
 
-LOCALFUNC tMacErr DeleteFile_v2(Dir_R *d, StringPtr s)
+LOCALFUNC MacErr_t DeleteFile_v2(Dir_R *d, StringPtr s)
 {
-	tMacErr err;
+	MacErr_t err;
 	HParamBlockRec r;
 
 	r.fileParam.ioCompletion = NULL;
@@ -4038,9 +4038,9 @@ LOCALFUNC tMacErr DeleteFile_v2(Dir_R *d, StringPtr s)
 	return err;
 }
 
-LOCALFUNC tMacErr CreateFileOverWrite_v2(Dir_R *d, StringPtr s)
+LOCALFUNC MacErr_t CreateFileOverWrite_v2(Dir_R *d, StringPtr s)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	err = CreateFile_v2(d, s);
 	if (mnvm_dupFNErr == err) {
@@ -4052,10 +4052,10 @@ LOCALFUNC tMacErr CreateFileOverWrite_v2(Dir_R *d, StringPtr s)
 	return err;
 }
 
-LOCALFUNC tMacErr FileOpen_v2(Dir_R *d, StringPtr s,
+LOCALFUNC MacErr_t FileOpen_v2(Dir_R *d, StringPtr s,
 	char Permssn, short *refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 	HParamBlockRec r;
 
 	r.ioParam.ioCompletion = NULL;
@@ -4086,16 +4086,16 @@ LOCALFUNC tMacErr FileOpen_v2(Dir_R *d, StringPtr s,
 	return err;
 }
 
-LOCALFUNC tMacErr FileOpenWrite_v2(Dir_R *d, StringPtr s,
+LOCALFUNC MacErr_t FileOpenWrite_v2(Dir_R *d, StringPtr s,
 	short *refnum)
 {
 	return FileOpen_v2(d, s, (char)fsWrPerm, refnum);
 }
 
-LOCALFUNC tMacErr OpenOverWriteFile_v2(Dir_R *d, StringPtr s,
+LOCALFUNC MacErr_t OpenOverWriteFile_v2(Dir_R *d, StringPtr s,
 	short *refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	err = CreateFileOverWrite_v2(d, s);
 	if (mnvm_noErr == err) {
@@ -4110,7 +4110,7 @@ LOCALFUNC tMacErr OpenOverWriteFile_v2(Dir_R *d, StringPtr s,
 	return err;
 }
 
-LOCALFUNC tMacErr OpenOverWriteFileCStr(Dir_R *d, char *name,
+LOCALFUNC MacErr_t OpenOverWriteFileCStr(Dir_R *d, char *name,
 	short *refnum)
 {
 	Str255 s;
@@ -4121,9 +4121,9 @@ LOCALFUNC tMacErr OpenOverWriteFileCStr(Dir_R *d, char *name,
 
 #define ActvCodeFileName "act_1"
 
-LOCALFUNC tMacErr OpenActvCodeFile(short *refnum)
+LOCALFUNC MacErr_t OpenActvCodeFile(short *refnum)
 {
-	tMacErr err;
+	MacErr_t err;
 	Dir_R PrefRef;
 	Dir_R GryphelRef;
 	Dir_R ActRef;
@@ -4142,9 +4142,9 @@ LOCALFUNC tMacErr OpenActvCodeFile(short *refnum)
 	return err;
 }
 
-LOCALFUNC tMacErr ActvCodeFileLoad(uint8_t * p)
+LOCALFUNC MacErr_t ActvCodeFileLoad(uint8_t * p)
 {
-	tMacErr err;
+	MacErr_t err;
 	short refnum;
 
 	if (CheckSavetMacErr(OpenActvCodeFile(&refnum))) {
@@ -4156,9 +4156,9 @@ LOCALFUNC tMacErr ActvCodeFileLoad(uint8_t * p)
 	return err;
 }
 
-LOCALFUNC tMacErr ActvCodeFileSave(uint8_t * p)
+LOCALFUNC MacErr_t ActvCodeFileSave(uint8_t * p)
 {
-	tMacErr err;
+	MacErr_t err;
 	short refnum;
 	Dir_R PrefRef;
 	Dir_R GryphelRef;
diff --git a/src/UI/UNIX/OSGLUXWN.c b/src/UI/UNIX/OSGLUXWN.c
index 91eca6c..ee0cc36 100644
--- a/src/UI/UNIX/OSGLUXWN.c
+++ b/src/UI/UNIX/OSGLUXWN.c
@@ -78,9 +78,9 @@ LOCALVAR char *app_parent = NULL;
 LOCALVAR char *app_name = NULL;
 #endif
 
-LOCALFUNC tMacErr ChildPath(char *x, char *y, char **r)
+LOCALFUNC MacErr_t ChildPath(char *x, char *y, char **r)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	int nx = strlen(x);
 	int ny = strlen(y);
 	{
@@ -108,9 +108,9 @@ LOCALFUNC tMacErr ChildPath(char *x, char *y, char **r)
 }
 
 #if IncludeSonyNew
-LOCALFUNC tMacErr FindOrMakeChild(char *x, char *y, char **r)
+LOCALFUNC MacErr_t FindOrMakeChild(char *x, char *y, char **r)
 {
-	tMacErr err;
+	MacErr_t err;
 	struct stat folder_info;
 	char *r0;
 
@@ -350,7 +350,7 @@ LOCALVAR const uint8_t Native2MacRomanTab[] = {
 #endif
 
 #if IncludePbufs
-LOCALFUNC tMacErr NativeTextToMacRomanPbuf(char *x, tPbuf *r)
+LOCALFUNC MacErr_t NativeTextToMacRomanPbuf(char *x, tPbuf *r)
 {
 	if (NULL == x) {
 		return mnvm_miscErr;
@@ -502,11 +502,11 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	uint32_t NewSony_Count = 0;
 
@@ -529,9 +529,9 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return err; /*& figure out what really to return &*/
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	long v;
 
@@ -614,7 +614,7 @@ LOCALPROC UnlockFile(FILE *refnum)
 }
 #endif
 
-LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
+LOCALFUNC MacErr_t vSonyEject0(tDrive Drive_No, bool deleteit)
 {
 	FILE *refnum = Drives[Drive_No];
 
@@ -643,13 +643,13 @@ LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
 	return mnvm_noErr;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, false);
 }
 
 #if IncludeSonyNew
-GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEjectDelete(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, true);
 }
@@ -667,7 +667,7 @@ LOCALPROC UnInitDrives(void)
 }
 
 #if IncludeSonyGetName
-GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t vSonyGetName(tDrive Drive_No, tPbuf *r)
 {
 	char *drivepath = DriveNames[Drive_No];
 	if (NULL == drivepath) {
@@ -744,9 +744,9 @@ LOCALFUNC bool Sony_Insert1(char *drivepath, bool silentfail)
 	return false;
 }
 
-LOCALFUNC tMacErr LoadMacRomFrom(char *path)
+LOCALFUNC MacErr_t LoadMacRomFrom(char *path)
 {
-	tMacErr err;
+	MacErr_t err;
 	FILE *ROM_File;
 	int File_Size;
 
@@ -894,7 +894,7 @@ LOCALPROC MakeNewDisk(uint32_t L, char *drivename)
 	if (NULL == d) {
 		MakeNewDisk0(L, drivename); /* in current directory */
 	} else {
-		tMacErr err;
+		MacErr_t err;
 		char *t = NULL;
 		char *t2 = NULL;
 
@@ -929,9 +929,9 @@ LOCALVAR char *rom_path = NULL;
 #include <unistd.h>
 #endif
 
-LOCALFUNC tMacErr FindUserHomeFolder(char **r)
+LOCALFUNC MacErr_t FindUserHomeFolder(char **r)
 {
-	tMacErr err;
+	MacErr_t err;
 	char *s;
 #if 0
 	struct passwd *user;
@@ -967,9 +967,9 @@ LOCALFUNC tMacErr FindUserHomeFolder(char **r)
 	return err;
 }
 
-LOCALFUNC tMacErr LoadMacRomFromHome(void)
+LOCALFUNC MacErr_t LoadMacRomFromHome(void)
 {
-	tMacErr err;
+	MacErr_t err;
 	char *s;
 	char *t = NULL;
 	char *t2 = NULL;
@@ -991,9 +991,9 @@ LOCALFUNC tMacErr LoadMacRomFromHome(void)
 }
 
 #ifdef CanGetAppPath
-LOCALFUNC tMacErr LoadMacRomFromAppPar(void)
+LOCALFUNC MacErr_t LoadMacRomFromAppPar(void)
 {
-	tMacErr err;
+	MacErr_t err;
 	char *d =
 #ifdef CanGetAppPath
 		(NULL == d_arg) ? app_parent :
@@ -1019,7 +1019,7 @@ LOCALFUNC tMacErr LoadMacRomFromAppPar(void)
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if ((NULL == rom_path)
 		|| (mnvm_fnfErr == (err = LoadMacRomFrom(rom_path))))
@@ -2477,9 +2477,9 @@ LOCALPROC FreeClipBuffer(void)
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
+GLOBALOSGLUFUNC MacErr_t HTCEexport(tPbuf i)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	FreeClipBuffer();
 	if (MacRomanTextToNativePtr(i, false,
@@ -2593,7 +2593,7 @@ LOCALPROC HTCEimport_do(void)
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEimport(tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t HTCEimport(tPbuf *r)
 {
 	HTCEimport_do();
 
diff --git a/src/UI/WIN32/OSGLUWIN.c b/src/UI/WIN32/OSGLUWIN.c
index 1903af7..ad7bb4a 100644
--- a/src/UI/WIN32/OSGLUWIN.c
+++ b/src/UI/WIN32/OSGLUWIN.c
@@ -270,10 +270,10 @@ LOCALVAR HGLOBAL PbufDat[NumPbufs];
 #endif
 
 #if IncludePbufs
-LOCALFUNC tMacErr PbufNewFromHandle(HGLOBAL h, uint32_t count, tPbuf *r)
+LOCALFUNC MacErr_t PbufNewFromHandle(HGLOBAL h, uint32_t count, tPbuf *r)
 {
 	tPbuf i;
-	tMacErr err;
+	MacErr_t err;
 
 	if (! FirstFreePbuf(&i)) {
 		(void) GlobalFree(h);
@@ -290,10 +290,10 @@ LOCALFUNC tMacErr PbufNewFromHandle(HGLOBAL h, uint32_t count, tPbuf *r)
 #endif
 
 #if IncludePbufs
-GLOBALOSGLUFUNC tMacErr PbufNew(uint32_t count, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t PbufNew(uint32_t count, tPbuf *r)
 {
 	HGLOBAL h;
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	h = GlobalAlloc(GMEM_DDESHARE | GMEM_ZEROINIT, count);
 	if (h != NULL) {
@@ -3578,7 +3578,7 @@ LOCALVAR const uint8_t Native2MacRomanTab[] = {
 };
 
 #if IncludePbufs
-LOCALFUNC tMacErr NativeTextToMacRomanPbuf(HGLOBAL x, tPbuf *r)
+LOCALFUNC MacErr_t NativeTextToMacRomanPbuf(HGLOBAL x, tPbuf *r)
 {
 #if UseUni
 #define UnsignedChar uint16_t
@@ -3589,7 +3589,7 @@ LOCALFUNC tMacErr NativeTextToMacRomanPbuf(HGLOBAL x, tPbuf *r)
 	LPTSTR p1;
 	uint32_t n;
 	UnsignedChar v;
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	p1 = GlobalLock(x);
 	if (p1 != NULL) {
@@ -3738,10 +3738,10 @@ LOCALFUNC bool MacRomanTextToNativeHand(tPbuf Pbuf_no,
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
+GLOBALOSGLUFUNC MacErr_t HTCEexport(tPbuf i)
 {
 	HGLOBAL h;
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	if (MacRomanTextToNativeHand(i, false, &h)) {
 		if (! OpenClipboard(MainWnd)) {
@@ -3772,9 +3772,9 @@ GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEimport(tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t HTCEimport(tPbuf *r)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	if (IsClipboardFormatAvailable(CF_TEXT)) {
 		if (! OpenClipboard(MainWnd)) {
@@ -3830,13 +3830,13 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
 	HANDLE refnum;
 	DWORD newL;
-	tMacErr result;
+	MacErr_t result;
 	DWORD BytesTransferred = 0;
 
 	refnum = Drives[Drive_No];
@@ -3895,9 +3895,9 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return result;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
-	tMacErr result;
+	MacErr_t result;
 	DWORD L;
 
 	L = GetFileSize(Drives[Drive_No], nullpr);
@@ -3911,7 +3911,7 @@ GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 	return result;
 }
 
-LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
+LOCALFUNC MacErr_t vSonyEject0(tDrive Drive_No, bool deleteit)
 {
 	HANDLE refnum = Drives[Drive_No];
 
@@ -3946,13 +3946,13 @@ LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
 	return mnvm_noErr;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, false);
 }
 
 #if IncludeSonyNew
-GLOBALOSGLUFUNC tMacErr vSonyEjectDelete(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEjectDelete(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, true);
 }
@@ -3996,10 +3996,10 @@ LOCALFUNC bool LPTSTRtoHand(LPTSTR s, HGLOBAL *r)
 #endif
 
 #if IncludeSonyGetName
-GLOBALOSGLUFUNC tMacErr vSonyGetName(tDrive Drive_No, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t vSonyGetName(tDrive Drive_No, tPbuf *r)
 {
 	WIN32_FIND_DATA fd;
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	HGLOBAL ph = DriveNames[Drive_No];
 	if (NULL != ph) {
 		LPTSTR drivepath = GlobalLock(ph);
@@ -4295,12 +4295,12 @@ LOCALFUNC bool FileExists(LPTSTR pathName, bool *directory)
 	return IsOk;
 }
 
-LOCALFUNC tMacErr ResolveNamedChild0(LPTSTR pathName,
+LOCALFUNC MacErr_t ResolveNamedChild0(LPTSTR pathName,
 	LPTSTR Child, bool *directory)
 {
 	size_t newlen;
 	size_t oldlen = _tcslen(pathName);
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	newlen = oldlen + 1 + _tcslen(Child);
 	if (newlen + 1 < _MAX_PATH) {
@@ -4330,7 +4330,7 @@ LOCALFUNC tMacErr ResolveNamedChild0(LPTSTR pathName,
 	return err;
 }
 
-LOCALFUNC tMacErr ResolveNamedChild(LPTSTR pathName,
+LOCALFUNC MacErr_t ResolveNamedChild(LPTSTR pathName,
 	char *Child, bool *directory)
 {
 	TCHAR Child0[ClStrMaxLength + 1];
@@ -4363,7 +4363,7 @@ LOCALFUNC bool MakeNamedChildDir(LPTSTR pathName, char *Child)
 {
 	bool directory;
 	bool IsOk = false;
-	tMacErr err = ResolveNamedChild(pathName, Child, &directory);
+	MacErr_t err = ResolveNamedChild(pathName, Child, &directory);
 
 	if (mnvm_noErr == err) {
 		IsOk = directory;
@@ -4648,7 +4648,7 @@ LOCALPROC MakeNewDisk(uint32_t L, HGLOBAL NewDiskNameDat)
 		LPTSTR p = GlobalLock(NewDiskNameDat);
 
 		if (p != NULL) {
-			tMacErr err = ResolveNamedChild0(pathName, p,
+			MacErr_t err = ResolveNamedChild0(pathName, p,
 				&directory);
 
 			if (mnvm_fnfErr == err) {
diff --git a/src/UI/XPLAT/OSGLUGTK.c b/src/UI/XPLAT/OSGLUGTK.c
index d011383..abeb2ef 100644
--- a/src/UI/XPLAT/OSGLUGTK.c
+++ b/src/UI/XPLAT/OSGLUGTK.c
@@ -149,7 +149,7 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
@@ -170,14 +170,14 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return mnvm_noErr; /*& figure out what really to return &*/
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
 	fseek(Drives[Drive_No], 0, SEEK_END);
 	*Sony_Count = ftell(Drives[Drive_No]);
 	return mnvm_noErr; /*& figure out what really to return &*/
 }
 
-LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
+LOCALFUNC MacErr_t vSonyEject0(tDrive Drive_No, bool deleteit)
 {
 	DiskEjectedNotify(Drive_No);
 
@@ -188,7 +188,7 @@ LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
 	return mnvm_noErr;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, false);
 }
@@ -242,9 +242,9 @@ LOCALFUNC bool Sony_Insert1(char *drivepath, bool silentfail)
 	return false;
 }
 
-LOCALFUNC tMacErr LoadMacRomFrom(char *path)
+LOCALFUNC MacErr_t LoadMacRomFrom(char *path)
 {
-	tMacErr err;
+	MacErr_t err;
 	FILE *ROM_File;
 	int File_Size;
 
@@ -319,7 +319,7 @@ LOCALVAR char *rom_path = NULL;
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if ((NULL == rom_path)
 		|| (mnvm_fnfErr == (err = LoadMacRomFrom(rom_path))))
diff --git a/src/UI/XPLAT/OSGLUSD2.c b/src/UI/XPLAT/OSGLUSD2.c
index 696af80..1b5d6f9 100644
--- a/src/UI/XPLAT/OSGLUSD2.c
+++ b/src/UI/XPLAT/OSGLUSD2.c
@@ -60,9 +60,9 @@ LOCALVAR char *pref_dir = NULL;
 #define PathSep '/'
 #endif
 
-LOCALFUNC tMacErr ChildPath(char *x, char *y, char **r)
+LOCALFUNC MacErr_t ChildPath(char *x, char *y, char **r)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	int nx = strlen(x);
 	int ny = strlen(y);
 	{
@@ -241,11 +241,11 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FilePtr refnum = Drives[Drive_No];
 	uint32_t NewSony_Count = 0;
 
@@ -268,9 +268,9 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return err; /*& figure out what really to return &*/
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FilePtr refnum = Drives[Drive_No];
 	long v;
 
@@ -285,7 +285,7 @@ GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 	return err; /*& figure out what really to return &*/
 }
 
-LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
+LOCALFUNC MacErr_t vSonyEject0(tDrive Drive_No, bool deleteit)
 {
 	FilePtr refnum = Drives[Drive_No];
 
@@ -297,7 +297,7 @@ LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
 	return mnvm_noErr;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, false);
 }
@@ -359,9 +359,9 @@ LOCALFUNC bool Sony_Insert1(char *drivepath, bool silentfail)
 	return false;
 }
 
-LOCALFUNC tMacErr LoadMacRomFrom(char *path)
+LOCALFUNC MacErr_t LoadMacRomFrom(char *path)
 {
-	tMacErr err;
+	MacErr_t err;
 	FilePtr ROM_File;
 	int File_Size;
 
@@ -465,9 +465,9 @@ LOCALFUNC bool LoadInitialImages(void)
 LOCALVAR char *rom_path = NULL;
 
 #if CanGetAppPath
-LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
+LOCALFUNC MacErr_t LoadMacRomFromPrefDir(void)
 {
-	tMacErr err;
+	MacErr_t err;
 	char *t = NULL;
 	char *t2 = NULL;
 
@@ -496,9 +496,9 @@ LOCALFUNC tMacErr LoadMacRomFromPrefDir(void)
 #endif
 
 #if CanGetAppPath
-LOCALFUNC tMacErr LoadMacRomFromAppPar(void)
+LOCALFUNC MacErr_t LoadMacRomFromAppPar(void)
 {
-	tMacErr err;
+	MacErr_t err;
 	char *d = (NULL == d_arg) ? app_parent : d_arg;
 	char *t = NULL;
 
@@ -522,7 +522,7 @@ LOCALFUNC tMacErr LoadMacRomFromAppPar(void)
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if ((NULL == rom_path)
 		|| (mnvm_fnfErr == (err = LoadMacRomFrom(rom_path))))
@@ -2603,9 +2603,9 @@ LOCALPROC MacRoman2UniCodeData(uint8_t *s, uimr L, char *t)
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
+GLOBALOSGLUFUNC MacErr_t HTCEexport(tPbuf i)
 {
-	tMacErr err;
+	MacErr_t err;
 	char *p;
 	uint8_t * s = PbufDat[i];
 	uimr L = PbufSize[i];
@@ -2630,9 +2630,9 @@ GLOBALOSGLUFUNC tMacErr HTCEexport(tPbuf i)
 #endif
 
 #if IncludeHostTextClipExchange
-LOCALFUNC tMacErr UniCodeStrLength(char *s, uimr *r)
+LOCALFUNC MacErr_t UniCodeStrLength(char *s, uimr *r)
 {
-	tMacErr err;
+	MacErr_t err;
 	uint8_t t;
 	uint8_t t2;
 	char *p = s;
@@ -2979,7 +2979,7 @@ LOCALFUNC uint8_t UniCodePoint2MacRoman(uint32_t x)
 #if IncludeHostTextClipExchange
 LOCALPROC UniCodeStr2MacRoman(char *s, char *r)
 {
-	tMacErr err;
+	MacErr_t err;
 	uint8_t t;
 	uint8_t t2;
 	uint8_t t3;
@@ -3054,9 +3054,9 @@ label_retry:
 #endif
 
 #if IncludeHostTextClipExchange
-GLOBALOSGLUFUNC tMacErr HTCEimport(tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t HTCEimport(tPbuf *r)
 {
-	tMacErr err;
+	MacErr_t err;
 	uimr L;
 	char *s = NULL;
 	tPbuf t = NotAPbuf;
diff --git a/src/UI/XPLAT/OSGLUSDL.c b/src/UI/XPLAT/OSGLUSDL.c
index 320c15d..9c7bb04 100644
--- a/src/UI/XPLAT/OSGLUSDL.c
+++ b/src/UI/XPLAT/OSGLUSDL.c
@@ -131,11 +131,11 @@ LOCALPROC InitDrives(void)
 	}
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
+GLOBALOSGLUFUNC MacErr_t vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	tDrive Drive_No, uint32_t Sony_Start, uint32_t Sony_Count,
 	uint32_t *Sony_ActCount)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	uint32_t NewSony_Count = 0;
 
@@ -158,9 +158,9 @@ GLOBALOSGLUFUNC tMacErr vSonyTransfer(bool IsWrite, uint8_t * Buffer,
 	return err; /*& figure out what really to return &*/
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
+GLOBALOSGLUFUNC MacErr_t vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 	FILE *refnum = Drives[Drive_No];
 	long v;
 
@@ -175,7 +175,7 @@ GLOBALOSGLUFUNC tMacErr vSonyGetSize(tDrive Drive_No, uint32_t *Sony_Count)
 	return err; /*& figure out what really to return &*/
 }
 
-LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
+LOCALFUNC MacErr_t vSonyEject0(tDrive Drive_No, bool deleteit)
 {
 	FILE *refnum = Drives[Drive_No];
 
@@ -187,7 +187,7 @@ LOCALFUNC tMacErr vSonyEject0(tDrive Drive_No, bool deleteit)
 	return mnvm_noErr;
 }
 
-GLOBALOSGLUFUNC tMacErr vSonyEject(tDrive Drive_No)
+GLOBALOSGLUFUNC MacErr_t vSonyEject(tDrive Drive_No)
 {
 	return vSonyEject0(Drive_No, false);
 }
@@ -249,9 +249,9 @@ LOCALFUNC bool Sony_Insert1(char *drivepath, bool silentfail)
 	return false;
 }
 
-LOCALFUNC tMacErr LoadMacRomFrom(char *path)
+LOCALFUNC MacErr_t LoadMacRomFrom(char *path)
 {
-	tMacErr err;
+	MacErr_t err;
 	FILE *ROM_File;
 	int File_Size;
 
@@ -335,7 +335,7 @@ LOCALVAR char *rom_path = NULL;
 
 LOCALFUNC bool LoadMacRom(void)
 {
-	tMacErr err;
+	MacErr_t err;
 
 	if ((NULL == rom_path)
 		|| (mnvm_fnfErr == (err = LoadMacRomFrom(rom_path))))
diff --git a/src/UTIL/PBUFSTDC.h b/src/UTIL/PBUFSTDC.h
index c5439c2..da8c8ee 100644
--- a/src/UTIL/PBUFSTDC.h
+++ b/src/UTIL/PBUFSTDC.h
@@ -24,10 +24,10 @@ LOCALVAR void *PbufDat[NumPbufs];
 #endif
 
 #if IncludePbufs
-LOCALFUNC tMacErr PbufNewFromPtr(void *p, uint32_t count, tPbuf *r)
+LOCALFUNC MacErr_t PbufNewFromPtr(void *p, uint32_t count, tPbuf *r)
 {
 	tPbuf i;
-	tMacErr err;
+	MacErr_t err;
 
 	if (! FirstFreePbuf(&i)) {
 		free(p);
@@ -54,9 +54,9 @@ LOCALPROC PbufKillToPtr(void **p, uint32_t *count, tPbuf r)
 #endif
 
 #if IncludePbufs
-GLOBALOSGLUFUNC tMacErr PbufNew(uint32_t count, tPbuf *r)
+GLOBALOSGLUFUNC MacErr_t PbufNew(uint32_t count, tPbuf *r)
 {
-	tMacErr err = mnvm_miscErr;
+	MacErr_t err = mnvm_miscErr;
 
 	void *p = calloc(1, count);
 	if (NULL != p) {