gcc problem

[Peter Pissias]

Exw to exhs provlhma:

kanontas compile (enws paragomenou apo to flex arxeiou) enw
pernaei to stadio tou compilation exei provlhma sto linking.
to output einai to exhs: 

root at plutonas:~# gcc lex.yy.c
/tmp/cc5G3Sdj.o: In function `yylex':
/tmp/cc5G3Sdj.o(.text+0x43b): undefined reference to `yywrap'
/tmp/cc5G3Sdj.o: In function `input':
/tmp/cc5G3Sdj.o(.text+0xb42): undefined reference to `yywrap'
collect2: ld returned 1 exit status

exw : slackware 7.1, kernel 2.4.10 , gcc 3.0

Exei kaneis idea ti ftaiei?

Efxaristw.
Petros