Problem with Raw Socket libraries

[Badedas]

I've this simple declaration in a raw socket program:
setsockopt(sock,IPPROTO_IP,IP_HDRINCL,&bol,sizeof(bol))

but I got this error:
`IP_HDRINCL' undeclared

What's the problem??
Why I can't find IP_HDRINCL in not any library??

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