diff --git a/wpcap/PRJ/build_scanner_parser.bat b/wpcap/PRJ/build_scanner_parser.bat
index 31786d596..54cba739d 100644
--- a/wpcap/PRJ/build_scanner_parser.bat
+++ b/wpcap/PRJ/build_scanner_parser.bat
@@ -4,7 +4,7 @@ echo Building the libpcap parser and scanner...
 del /Q /F  ..\libpcap\grammar.c > nul 2> nul
 del /Q /F  ..\libpcap\tokdefs.h > nul 2> nul
 
-bison -y -p pcap_ -d ../libpcap/GRAMMAR.Y > nul
+win_bison -y -p pcap_ -d ../libpcap/GRAMMAR.Y > nul
 if not %ERRORLEVEL% == 0 (
 	echo failure in generating the grammar.
 	goto end
@@ -14,7 +14,7 @@ move y.tab.c ..\libpcap\grammar.c
 move y.tab.h ..\libpcap\tokdefs.h
 
 del /Q /F ..\libpcap\scanner.c >/nul 2>/nul
-flex -Ppcap_ -t  ../libpcap/scanner.l > ../libpcap/scanner.c
+win_flex -Ppcap_ -t  ../libpcap/scanner.l > ../libpcap/scanner.c
 
 if not %ERRORLEVEL% == 0 (
 	echo failure in generating the scanner.