about ioctl(...) in solaris10

sgs

In sorlaris10:

#include<unistd.h>;
......
    ioctl(sockfd,SIOCGIFADDR,&ifreq);
.......

when i compiler these code,show me:SIOCGIFADDR undeclared(first use in this function)? why?
  SIOCSIFDSTADDR or SIOCSIFNETMASK....,these request parameters all get the same results!
   why?

sgs

thnaks everyone:
    In fact ,those codes must include <sys/sockio.h>;,is ok so that!
    i spend much time to find the result!
     
                            2005.03.10