text: CAP_BIND(3N) CAP_BIND(3N)
  cap_bind - bind a privileged name to a socket
  #include <cap_net.h>
  int cap_bind(int s, const struct sockaddr *name,
  int namelen);
  cap_bind asserts appropriate privilege when assigning a name to a socket.
  This is necessary when a process wishes to bind an Internet Domain socket
  to a port whose numeric value is less than 1024, for example.
  If _POSIX_CAP is in effect, a process calling this function should have
  CAP_PRIV_PORT capability in the permitted vector of its capability set.
  cap_bind returns 0 if successful, -1 otherwise.
  cap_bind has the same error codes as bind(2).
  capability(4), bind(2), sysconf(3c).
  PPPPaaaaggggeeee 1111