Let's say I see 
	ioctl(s, SIOCFOOBAR, &somecutestruct)

  in some code.

  How do I RTFM on this?
  grep in /usr/share/man ?
  In this case, the specific one is SIOCGIFMTU, and grep turns up
negative.

  I have to grep in /usr/src/sys/net to find something.
  In this case, I think that SIOCGIFMTU is actually missing from netintro(4).

   :!mcr!:            |  Network and security consulting/contract programming
   Michael Richardson |   I do IPsec policy code for SSH <http://www.ssh.fi/>
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