Fixed to take in account the different interpretation of double

quootes on UNIX-like shells vs DOS-like command interpreters.

src/makefile.dj

@@ -39,6 +39,14 @@ CFLAGS += -DUSE_ENVIRONMENT
 PROGRAM  = curl.exe
 OBJECTS += $(addprefix $(OBJ_DIR)/, $(CSOURCES:.c=.o))
 
+ifneq ($(findstring COMMAND.COM,$(SHELL)),COMMAND.COM)
+  ifneq ($(findstring CMD.EXE,$(SHELL)),CMD.EXE)
+    ifneq ($(findstring 4DOS.COM,$(SHELL)),4DOS.COM)
+      IS_UNIX_SHELL = 1
+    endif
+  endif
+endif
+
 all: $(OBJ_DIR) config.h $(PROGRAM)
 	@echo Welcome to cURL
 
@@ -46,7 +54,11 @@ $(PROGRAM): $(OBJECTS) ../lib/libcurl.a
 	$(CC) -o $@ $^ $(LDFLAGS) $(EX_LIBS)
 
 config.h:
+ifeq ($(IS_UNIX_SHELL),1)
 	@echo '#include "../lib/config.dos"' > $@
+else
+	@echo #include "../lib/config.dos" > $@
+endif
 
 #
 # groff 1.18+ requires "-P -c"