diff --git a/src/OWDOS16.mak b/src/OWDOS16.mak
old mode 100644
new mode 100755
index d8af995..f4e687b
--- a/src/OWDOS16.mak
+++ b/src/OWDOS16.mak
@@ -1,13 +1,29 @@
 
 # this makefile creates a DOS 16-bit real-mode version of JWasm (JWASMR.EXE).
-# tools used:
-# - Open Watcom v1.8/v1.9
+# Open Watcom v1.8-v1.9 may be used.
 
 name = JWasm
 
-!ifndef WATCOM
-WATCOM = \Watcom
+# Detect which platform we're _running_ on, to use proper
+# directory separator.
+
+!ifdef __LINUX__
+DS=/
+!else
+DS=\
+!endif
+
+# When building _on_ Linux, use the script in the Watcom root
+# directory to set up the proper environment variables. Call
+# this script as ¨. owsetevn.sh¨ The WATCOM directory
+# declarations should not end with a / or \.
+
+!ifndef %WATCOM
+WATCOM=$(DS)Watcom
+!else
+WATCOM=$(%WATCOM)
 !endif
+
 !ifndef DEBUG
 DEBUG=0
 !endif
@@ -18,16 +34,23 @@ OUTD=OWDOS16D
 OUTD=OWDOS16R
 !endif
 
-inc_dirs  = -IH -I$(WATCOM)\H
+# Linux is case-sensitive, so use lower case h for the Watcom includes.
+inc_dirs  = -IH -I$(WATCOM)$(DS)h
 
 # to track memory leaks, the Open Watcom TRMEM module can be included.
-# it's useful only if FASTMEM=0 is set, though, otherwise most allocs 
+# it's useful only if FASTMEM=0 is set, though, otherwise most allocs
 # won't use the C heap.
 !ifndef TRMEM
 TRMEM=0
 !endif
 
-LINK = $(WATCOM)\binnt\wlink.exe
+!ifdef JWLINK
+LINK = jwlink.exe
+c_flags = -zc
+!else
+LINK = wlink
+c_flags = -zc
+!endif
 
 #cflags stuff
 #########
@@ -42,49 +65,48 @@ extra_c_flags += -od -d2 -DDEBUG_OUT
 extra_c_flags += -obmilrs -s -DNDEBUG
 !endif
 
-#########
-
 !if $(DEBUG)
 LOPTD = debug dwarf op symfile
 !endif
 
 lflagsd = $(LOPTD) sys dos op map=$^*, stack=0x8400
 
-CC=$(WATCOM)\binnt\wcc -q -0 -w3 -zc -ml -bc -bt=dos $(inc_dirs) $(extra_c_flags) -fo$@ -DFASTMEM=0 -DFASTPASS=0 -DCOFF_SUPPORT=0 -DELF_SUPPORT=0 -DAMD64_SUPPORT=0 -DSSSE3SUPP=0 -DSSE4SUPP=0 -DOWFC_SUPPORT=0 -DDLLIMPORT=0 -DAVXSUPP=0 -DPE_SUPPORT=0 -DVMXSUPP=0 -DSVMSUPP=0 -DCVOSUPP=0 -DCOMDATSUPP=0 -DSTACKBASESUPP=0 -zt=12000
+CC = wcc -q -0 -w3 -zc -ml -bc -bt=dos $(inc_dirs) $(extra_c_flags) -fo$@ -DFASTMEM=0 -DFASTPASS=0 -DCOFF_SUPPORT=0 -DELF_SUPPORT=0 -DAMD64_SUPPORT=0 -DSSSE3SUPP=0 -DSSE4SUPP=0 -DOWFC_SUPPORT=0 -DDLLIMPORT=0 -DAVXSUPP=0 -DPE_SUPPORT=0 -DVMXSUPP=0 -DSVMSUPP=0 -DCVOSUPP=0 -DCOMDATSUPP=0 -DSTACKBASESUPP=0 -zt=12000
 
 .c{$(OUTD)}.obj:
-	@$(CC) $<
+    $(CC) $<
 
 proj_obj = &
 !include owmod.inc
 
 !if $(TRMEM)
-proj_obj += $(OUTD)/trmem.obj
+proj_obj += $(OUTD)$(DS)trmem.obj
 !endif
 
-ALL: $(OUTD) $(OUTD)/$(name)r.exe
+ALL: $(OUTD) $(OUTD)$(DS)$(name)r.exe
 
 $(OUTD):
-	@if not exist $(OUTD) mkdir $(OUTD)
+    @if not exist $(OUTD) mkdir $(OUTD)
 
-$(OUTD)/$(name)r.exe: $(OUTD)/$(name).lib $(OUTD)/main.obj
-	@set LIB=$(WATCOM)\Lib286;$(WATCOM)\Lib286\DOS
-	@$(LINK) $(lflagsd) file $(OUTD)/main.obj name $@ lib $(OUTD)/$(name).lib
+$(OUTD)$(DS)$(name)r.exe: $(OUTD)$(DS)$(name).lib $(OUTD)$(DS)main.obj
+    @set LIB=$(WATCOM)$(DS)Lib286;$(WATCOM)$(DS)Lib286$(DS)DOS
+    $(LINK) $(lflagsd) file $(OUTD)$(DS)main.obj name $@ lib $(OUTD)$(DS)$(name).lib
 
-$(OUTD)/$(name).lib: $(proj_obj)
-	@cd $(OUTD)
-	@wlib -q -n $(name).lib $(proj_obj:$(OUTD)/=+)
-	@cd ..
+$(OUTD)$(DS)$(name).lib: $(proj_obj)
+    @cd $(OUTD)
+    wlib -q -n $(name).lib $(proj_obj:$(OUTD)$(DS)=+)
+    @cd ..
 
-$(OUTD)/msgtext.obj: msgtext.c H/msgdef.h H/globals.h
-	@$(CC) msgtext.c
+$(OUTD)$(DS)msgtext.obj: msgtext.c H$(DS)msgdef.h H$(DS)globals.h
+    @$(CC) msgtext.c
 
-$(OUTD)/reswords.obj: reswords.c H/instruct.h H/special.h H/directve.h
-	@$(CC) reswords.c
+$(OUTD)$(DS)reswords.obj: reswords.c H$(DS)instruct.h H$(DS)special.h H$(DS)directve.h
+    @$(CC) reswords.c
 
 ######
 
 clean: .SYMBOLIC
-	@if exist $(OUTD)\*.obj        erase $(OUTD)\*.obj
-	@if exist $(OUTD)\$(name)r.exe erase $(OUTD)\$(name)r.exe
-	@if exist $(OUTD)\$(name)r.map erase $(OUTD)\$(name)r.map
+    @if exist $(OUTD)$(DS)*.obj        -rm $(OUTD)$(DS)*.obj
+    @if exist $(OUTD)$(DS)$(name)r.exe -rm $(OUTD)$(DS)$(name)r.exe
+    @if exist $(OUTD)$(DS)$(name)r.map -rm $(OUTD)$(DS)$(name)r.map
+    @if exist $(OUTD)$(DS)$(name).lib  -rm $(OUTD)$(DS)$(name).lib
diff --git a/src/OWLinux.mak b/src/OWLinux.mak
old mode 100644
new mode 100755
index 434088e..3abddef
--- a/src/OWLinux.mak
+++ b/src/OWLinux.mak
@@ -1,98 +1,127 @@
-
-# this makefile (WMake) creates the Linux binary of JWasm.
-# Open Watcom v1.8-v1.9 may be used.
-
-name = jwasm
-
-!ifndef WATCOM
-WATCOM=\Watcom
-!endif
-!ifndef DEBUG
-DEBUG=0
-!endif
-
-!ifndef OUTD
-!if $(DEBUG)
-OUTD=OWLinuxD
-!else
-OUTD=OWLinuxR
-!endif
-!endif
-
-# calling convention for compiler: s=Stack, r=Register
-CCV=r
-
-inc_dirs  = -IH -I$(WATCOM)\LH
-
-# to track memory leaks, the Open Watcom TRMEM module can be included
-!ifndef TRMEM
-TRMEM=0
-!endif
-
-!ifdef JWLINK
-LINK = jwlink.exe
-c_flags = -zc
-!else
-LINK = $(WATCOM)\Binnt\wlink.exe
-c_flags = -zc
-!endif
-
-#cflags stuff
-#########
-extra_c_flags =
-!if $(DEBUG)
-extra_c_flags += -od -d2 -DDEBUG_OUT
-!else
-extra_c_flags += -ot -s -DNDEBUG
-!endif
-
-!if $(TRMEM)
-extra_c_flags += -DTRMEM -DFASTMEM=0
-!endif
-
-#lflags stuff
-#########
-!if $(DEBUG)
-LOPTD = debug dwarf op symfile
-!endif
-
-CC = $(WATCOM)\Binnt\wcc386 -q -3$(CCV) $(c_flags) -bc -bt=linux $(inc_dirs) $(extra_c_flags) -fo$@
-
-.c{$(OUTD)}.obj:
-	$(CC) $<
-
-proj_obj = &
-!include owmod.inc
-
-!if $(TRMEM)
-proj_obj += $(OUTD)/trmem.obj
-!endif
-
-ALL: $(OUTD) $(OUTD)/$(name)
-
-$(OUTD):
-	@if not exist $(OUTD) mkdir $(OUTD)
-
-$(OUTD)/$(name) : $(OUTD)/main.obj $(proj_obj)
-	$(LINK) @<<
-format elf runtime linux
-$(LOPTD)
-libpath $(WATCOM)/lib386
-libpath $(WATCOM)/lib386/linux
-op map=$^*, norelocs, quiet, stack=0x20000
-file { $(OUTD)/main.obj $(proj_obj) }
-name $@.
-<<
-
-$(OUTD)/msgtext.obj: msgtext.c H/msgdef.h H/globals.h
-	$(CC) msgtext.c
-
-$(OUTD)/reswords.obj: reswords.c H/instruct.h H/special.h H/directve.h
-	$(CC) reswords.c
-
-######
-
-clean: .SYMBOLIC
-	@if exist $(OUTD)\*.    erase $(OUTD)\*.
-	@if exist $(OUTD)\*.obj erase $(OUTD)\*.obj
-	@if exist $(OUTD)\*.map erase $(OUTD)\*.map
+
+# this makefile (WMake) creates the Linux binary of JWasm (jwasm)
+# Open Watcom v1.8-v1.9 may be used.
+
+# Note that this makefile assumes that the OW environment is
+# set - the OW tools are to be found in the PATH and the INCLUDE
+# environment variable is set correctly.
+
+name = jwasm
+
+# Detect which platform we're _running_ on, to use proper
+# directory separator.
+
+!ifdef __LINUX__
+DS=/
+!else
+DS=\
+!endif
+
+# When building _on_ Linux, use the script in the Watcom root
+# directory to set up the proper environment variables. Call
+# this script as ¨. owsetevn.sh¨ The WATCOM directory
+# declarations should not end with a / or \.
+
+!ifndef %WATCOM
+WATCOM=$(DS)Watcom
+!else
+WATCOM=$(%WATCOM)
+!endif
+
+!ifndef DEBUG
+DEBUG=0
+!endif
+
+!if $(DEBUG)
+OUTD=OWLinuxD
+!else
+OUTD=OWLinuxR
+!endif
+
+# calling convention for compiler: s=Stack, r=Register
+CCV=r
+
+# Linux is case-sensitive, so use lower case h for the Watcom includes.
+inc_dirs  = -IH -I$(WATCOM)$(DS)lh
+
+# to track memory leaks, the Open Watcom TRMEM module can be included
+# it's useful only if FASTMEM=0 is set, though, otherwise most allocs
+# won't use the C heap.
+!ifndef TRMEM
+TRMEM=0
+!endif
+
+!ifdef JWLINK
+LINK = jwlink.exe
+c_flags = -zc
+!else
+LINK = wlink
+c_flags = -zc
+!endif
+
+#cflags stuff
+#########
+extra_c_flags =
+!if $(DEBUG)
+extra_c_flags += -od -d2 -DDEBUG_OUT
+!else
+extra_c_flags += -ot -s -DNDEBUG
+!endif
+
+!if $(TRMEM)
+extra_c_flags += -DTRMEM -DFASTMEM=0
+!endif
+
+!if $(DEBUG)
+LOPTD = debug dwarf op symfile
+!endif
+
+CC = wcc386 -q -3$(CCV) $(c_flags) -bc -bt=linux $(inc_dirs) $(extra_c_flags) -fo$@
+
+.c{$(OUTD)}.obj:
+    $(CC) $<
+
+proj_obj = &
+!include owmod.inc
+
+!if $(TRMEM)
+proj_obj += $(OUTD)$(DS)trmem.obj
+!endif
+
+ALL: $(OUTD) $(OUTD)$(DS)$(name)
+
+$(OUTD):
+    @if not exist $(OUTD) mkdir $(OUTD)
+
+$(OUTD)$(DS)$(name) : $(OUTD)$(DS)main.obj $(proj_obj)
+    $(LINK) @<<
+format elf runtime linux
+!if $(DEBUG)
+$(LOPTD)
+!endif
+libpath $(WATCOM)$(DS)lib386
+libpath $(WATCOM)$(DS)lib386$(DS)linux
+op map=$^*, norelocs, quiet, stack=0x20000
+file { $(OUTD)/main.obj $(proj_obj) }
+name $@
+<<
+
+$(OUTD)$(DS)msgtext.obj: msgtext.c H$(DS)msgdef.h H$(DS)globals.h
+    $(CC) msgtext.c
+
+$(OUTD)$(DS)reswords.obj: reswords.c H$(DS)instruct.h H$(DS)special.h H$(DS)directve.h
+    $(CC) reswords.c
+
+######
+# Under non-Linux, the link format "elf" forces a file name extension of .elf.
+# While this can be prevented by the NOEXTENSION link option, the resulting
+# file without extension will not be detected by the "exist" below, so a "clean"
+# leaves the file in place. Under Linux this detection works properly.
+# Watcom ought to have a internal (=platform independent) command to detect
+# the presence of such a file. E.g. %exist alllowing wildcards.
+
+clean: .SYMBOLIC
+    @if exist $(OUTD)$(DS)*     -rm $(OUTD)$(DS)*
+    @if exist $(OUTD)$(DS)*.elf -rm $(OUTD)$(DS)*.elf
+    @if exist $(OUTD)$(DS)*.obj -rm $(OUTD)$(DS)*.obj
+    @if exist $(OUTD)$(DS)*.map -rm $(OUTD)$(DS)*.map
diff --git a/src/OWOS2.mak b/src/OWOS2.mak
old mode 100644
new mode 100755
index e75bdcb..7c09758
--- a/src/OWOS2.mak
+++ b/src/OWOS2.mak
@@ -8,16 +8,35 @@
 # environment variable is set correctly.
 
 # 2011-07-09 -- rousseau at ecomstation.com -- fixed some stuff.
-# - Removed a trailing space after the '&' in the object-list on the 
+# - Removed a trailing space after the '&' in the object-list on the
 #   line with '$(OUTD)/omffixup.obj' that breaks wmake v1.9.
 # - Added '.SYMBOLIC' to 'clean:' to supress dependency checking.
-# - Added check for existence of files to 'clean:' to supress 
+# - Added check for existence of files to 'clean:' to supress
 #   abort when files are not found.
 # - Replaced 'erase' with 'del' in 'clean:' as this is the more common name.
 
-
 name = JWasm
 
+# Detect which platform we're _running_ on, to use proper
+# directory separator.
+
+!ifdef __LINUX__
+DS=/
+!else
+DS=\
+!endif
+
+# When building _on_ Linux, use the script in the Watcom root
+# directory to set up the proper environment variables. Call
+# this script as ¨. owsetevn.sh¨ The WATCOM directory
+# declarations should not end with a / or \.
+
+!ifndef %WATCOM
+WATCOM=$(DS)Watcom
+!else
+WATCOM=$(%WATCOM)
+!endif
+
 !ifndef DEBUG
 DEBUG=0
 !endif
@@ -32,9 +51,10 @@ OUTD=OWOS2R
 # r will create a slightly smaller binary
 CCV=r
 
-inc_dirs  = -IH
+# Linux is case-sensitive, so use lower case h for the Watcom includes.
+inc_dirs  = -IH -I$(WATCOM)$(DS)h -I$(WATCOM)$(DS)h$(DS)os2
 
-LINK = wlink.exe
+LINK = wlink
 
 #cflags stuff
 #########
@@ -47,7 +67,7 @@ extra_c_flags += -obmilrt -s -DNDEBUG
 
 #########
 
-LOPT = op quiet
+#LOPT = op quiet
 !if $(DEBUG)
 LOPTD = debug dwarf op symfile
 !endif
@@ -62,27 +82,27 @@ CC=wcc386 -q -3$(CCV) -bc -bt=os2 $(inc_dirs) $(extra_c_flags) -fo$@
 proj_obj = &
 !include owmod.inc
 
-TARGET1=$(OUTD)/$(name).exe
+TARGET1=$(OUTD)$(DS)$(name).exe
 
 ALL: $(OUTD) $(TARGET1)
 
 $(OUTD):
-	@if not exist $(OUTD) mkdir $(OUTD)
+    @if not exist $(OUTD) mkdir $(OUTD)
 
-$(TARGET1): $(OUTD)/main.obj $(proj_obj)
-	$(LINK) @<<
-$(lflagso) file { $(OUTD)/main.obj $(proj_obj) } name $@ op stack=0x20000
+$(TARGET1): $(OUTD)$(DS)main.obj $(proj_obj)
+    $(LINK) @<<
+$(lflagso) file { $(OUTD)$(DS)main.obj $(proj_obj) } name $@ op stack=0x20000
 <<
 
-$(OUTD)/msgtext.obj: msgtext.c H/msgdef.h H/globals.h
-	$(CC) msgtext.c
+$(OUTD)$(DS)msgtext.obj: msgtext.c H$(DS)msgdef.h H$(DS)globals.h
+    $(CC) msgtext.c
 
-$(OUTD)/reswords.obj: reswords.c H/instruct.h H/special.h H/directve.h
-	$(CC) reswords.c
+$(OUTD)$(DS)reswords.obj: reswords.c H$(DS)instruct.h H$(DS)special.h H$(DS)directve.h
+    $(CC) reswords.c
 
 ######
 
 clean: .SYMBOLIC
-	@if exist $(OUTD)\*.exe del $(OUTD)\*.exe
-	@if exist $(OUTD)\*.obj del $(OUTD)\*.obj
-	@if exist $(OUTD)\*.map del $(OUTD)\*.map
+    @if exist $(OUTD)$(DS)*.exe -rm $(OUTD)$(DS)*.exe
+    @if exist $(OUTD)$(DS)*.obj -rm $(OUTD)$(DS)*.obj
+    @if exist $(OUTD)$(DS)*.map -rm $(OUTD)$(DS)*.map
diff --git a/src/owmod.inc b/src/owmod.inc
index 7668ba5..1c10e5c 100644
--- a/src/owmod.inc
+++ b/src/owmod.inc
@@ -1,56 +1,56 @@
-$(OUTD)/apiemu.obj   &
-$(OUTD)/assemble.obj &
-$(OUTD)/assume.obj   &
-$(OUTD)/atofloat.obj &
-$(OUTD)/backptch.obj &
-$(OUTD)/bin.obj      &
-$(OUTD)/branch.obj   &
-$(OUTD)/cmdline.obj  &
-$(OUTD)/codegen.obj  &
-$(OUTD)/coff.obj     &
-$(OUTD)/condasm.obj  &
-$(OUTD)/context.obj  &
-$(OUTD)/cpumodel.obj &
-$(OUTD)/data.obj     &
-$(OUTD)/dbgcv.obj    &
-$(OUTD)/directiv.obj &
-$(OUTD)/elf.obj      &
-$(OUTD)/end.obj      &
-$(OUTD)/equate.obj   &
-$(OUTD)/errmsg.obj   &
-$(OUTD)/expans.obj   &
-$(OUTD)/expreval.obj &
-$(OUTD)/extern.obj   &
-$(OUTD)/fastpass.obj &
-$(OUTD)/fixup.obj    &
-$(OUTD)/fpfixup.obj  &
-$(OUTD)/hll.obj      &
-$(OUTD)/input.obj    &
-$(OUTD)/invoke.obj   &
-$(OUTD)/label.obj    &
-$(OUTD)/linnum.obj   &
-$(OUTD)/listing.obj  &
-$(OUTD)/loop.obj     &
-$(OUTD)/lqueue.obj   &
-$(OUTD)/macro.obj    &
-$(OUTD)/mangle.obj   &
-$(OUTD)/memalloc.obj &
-$(OUTD)/msgtext.obj  &
-$(OUTD)/omf.obj      &
-$(OUTD)/omffixup.obj &
-$(OUTD)/omfint.obj   &
-$(OUTD)/option.obj   &
-$(OUTD)/parser.obj   &
-$(OUTD)/posndir.obj  &
-$(OUTD)/preproc.obj  &
-$(OUTD)/proc.obj     &
-$(OUTD)/queue.obj    &
-$(OUTD)/reswords.obj &
-$(OUTD)/safeseh.obj  &
-$(OUTD)/segment.obj  &
-$(OUTD)/simsegm.obj  &
-$(OUTD)/string.obj   &
-$(OUTD)/symbols.obj  &
-$(OUTD)/tbyte.obj    &
-$(OUTD)/tokenize.obj &
-$(OUTD)/types.obj
+$(OUTD)$(DS)apiemu.obj   &
+$(OUTD)$(DS)assemble.obj &
+$(OUTD)$(DS)assume.obj   &
+$(OUTD)$(DS)atofloat.obj &
+$(OUTD)$(DS)backptch.obj &
+$(OUTD)$(DS)bin.obj      &
+$(OUTD)$(DS)branch.obj   &
+$(OUTD)$(DS)cmdline.obj  &
+$(OUTD)$(DS)codegen.obj  &
+$(OUTD)$(DS)coff.obj     &
+$(OUTD)$(DS)condasm.obj  &
+$(OUTD)$(DS)context.obj  &
+$(OUTD)$(DS)cpumodel.obj &
+$(OUTD)$(DS)data.obj     &
+$(OUTD)$(DS)dbgcv.obj    &
+$(OUTD)$(DS)directiv.obj &
+$(OUTD)$(DS)elf.obj      &
+$(OUTD)$(DS)end.obj      &
+$(OUTD)$(DS)equate.obj   &
+$(OUTD)$(DS)errmsg.obj   &
+$(OUTD)$(DS)expans.obj   &
+$(OUTD)$(DS)expreval.obj &
+$(OUTD)$(DS)extern.obj   &
+$(OUTD)$(DS)fastpass.obj &
+$(OUTD)$(DS)fixup.obj    &
+$(OUTD)$(DS)fpfixup.obj  &
+$(OUTD)$(DS)hll.obj      &
+$(OUTD)$(DS)input.obj    &
+$(OUTD)$(DS)invoke.obj   &
+$(OUTD)$(DS)label.obj    &
+$(OUTD)$(DS)linnum.obj   &
+$(OUTD)$(DS)listing.obj  &
+$(OUTD)$(DS)loop.obj     &
+$(OUTD)$(DS)lqueue.obj   &
+$(OUTD)$(DS)macro.obj    &
+$(OUTD)$(DS)mangle.obj   &
+$(OUTD)$(DS)memalloc.obj &
+$(OUTD)$(DS)msgtext.obj  &
+$(OUTD)$(DS)omf.obj      &
+$(OUTD)$(DS)omffixup.obj &
+$(OUTD)$(DS)omfint.obj   &
+$(OUTD)$(DS)option.obj   &
+$(OUTD)$(DS)parser.obj   &
+$(OUTD)$(DS)posndir.obj  &
+$(OUTD)$(DS)preproc.obj  &
+$(OUTD)$(DS)proc.obj     &
+$(OUTD)$(DS)queue.obj    &
+$(OUTD)$(DS)reswords.obj &
+$(OUTD)$(DS)safeseh.obj  &
+$(OUTD)$(DS)segment.obj  &
+$(OUTD)$(DS)simsegm.obj  &
+$(OUTD)$(DS)string.obj   &
+$(OUTD)$(DS)symbols.obj  &
+$(OUTD)$(DS)tbyte.obj    &
+$(OUTD)$(DS)tokenize.obj &
+$(OUTD)$(DS)types.obj