diff --git a/auto/defaults b/auto/defaults
index 4f033f3..b7d2008 100755
--- a/auto/defaults
+++ b/auto/defaults
@@ -10,6 +10,7 @@ DEFAULT_PROJECT_MAIL='utt@wmid.amu.edu.pl'
 DEFAULT_SHELL='/bin/sh'
 DEFAULT_CC='/usr/bin/gcc'
 DEFAULT_BISON='/usr/bin/bison'
+DEFAULT_FLEX='/usr/bin/flex'
 DEFAULT_RM='/bin/rm -f'
 DEFAULT_RMDIR='/bin/rm -rf'
 DEFAULT_TEST='/usr/bin/test'
diff --git a/auto/options b/auto/options
index 1f01a71..d08be05 100755
--- a/auto/options
+++ b/auto/options
@@ -13,6 +13,7 @@ if [ -z "$PROJECT_MAIL" ];      then PROJECT_MAIL=$DEFAULT_PROJECT_MAIL;
 if [ -z "$SHELL" ];             then SHELL=$DEFAULT_SHELL;                          fi
 if [ -z "$CC" ];                then CC=$DEFAULT_CC;                                fi
 if [ -z "$BISON" ];             then BISON=$DEFAULT_BISON;                          fi
+if [ -z "$FLEX" ];              then FLEX=$DEFAULT_FLEX;                            fi
 if [ -z "$RM" ];                then RM=$DEFAULT_RM;                                fi
 if [ -z "$RMDIR" ];             then RMDIR=$DEFAULT_RMDIR;                          fi
 if [ -z "$TEST" ];              then TEST=$DEFAULT_TEST;                            fi
@@ -64,6 +65,7 @@ do
     SHELL=*)            SHELL="$value"                            ;;
     CC=*)               CC="$value"                               ;;
     BISON=*)            BISON="$value"                            ;;
+    FLEX=*)             FLEX="$value"                             ;;
     RM=*)               RM="$value"                               ;;
     RMDIR=*)            RMDIR="$value"                            ;;
     TEST=*)             TEST="$value"                             ;;
diff --git a/auto/output/Makefile b/auto/output/Makefile
index 66f3fe4..b1fc037 100755
--- a/auto/output/Makefile
+++ b/auto/output/Makefile
@@ -7,6 +7,7 @@ cat << EOF > Makefile
 SHELL = $SHELL
 CC = $CC
 BISON = $BISON
+FLEX = $FLEX
 RM = $RM
 RMDIR = $RMDIR
 TEST = $TEST
@@ -37,12 +38,13 @@ ALL_CFLAGS = \$(CFLAGS)
 ALL_LDFLAGS = \$(LDFLAGS)
 ALL_LDLIBS = \$(LDLIBS)
 ALL_BFLAGS = \$(BFLAGS)
-ALL_FFLAGS = \$(FFLAGS)
+ALL_FFLAGS = -t \$(FFLAGS)
 
 VPATH = ./src
 
 PROGRAMS = tok
-TOK_OBJ_FILES = tok.o
+TOK_OBJ_FILES = tok.o tok_cmdline.o
+TOK_FLEX_FILES = tok.l
 CONFIG_FILES = src/config.h Makefile
 
 .SUFFIXES:
@@ -66,6 +68,7 @@ help:
 clean:
 	\$(RM) \$(PROGRAMS)
 	\$(RM) \$(TOK_OBJ_FILES)
+	\$(RM) \$(patsubst %.l,%.c,\$(TOK_FLEX_FILES))
 	#make -C app clean
 
 .PHONY: distclean
@@ -83,6 +86,9 @@ uninstall:
 %.o: %.c
 	\$(CC) -c \$< -o \$@ \$(ALL_CFLAGS)
 
+%.o: %.l
+	\$(FLEX) -t \$< > \$@
+
 %: %.o
 	\$(CC) \$? -o \$@ \$(ALL_LDFLAGS) \$(ALL_CFLAGS) \$(ALL_LDLIBS)
 
diff --git a/auto/summary b/auto/summary
index bf24619..29d938b 100755
--- a/auto/summary
+++ b/auto/summary
@@ -28,6 +28,7 @@ Configuration summary
   SHELL           : $SHELL
   CC              : $CC
   BISON           : $BISON
+  FLEX            : $FLEX
   RM              : $RM
   RMDIR           : $RMDIR
   TEST            : $TEST