| BINDRESVPORT(3) | Library Functions Manual | BINDRESVPORT(3) |
bindresvport,
bindresvport_sa — bind a
socket to a privileged IP port
Standard C Library (libc, -lc)
#include
<sys/types.h>
#include <rpc/rpc.h>
int
bindresvport(int
sd, struct sockaddr_in
*sin);
int
bindresvport_sa(int
sd, struct sockaddr
*sa);
The
bindresvport()
and
bindresvport_sa()
functions are used to bind a socket descriptor to a privileged IP port, that
is, a port number in the range 0-1023.
If sin is a pointer to a struct sockaddr_in then the appropriate fields in the structure should be defined. Note that sin->sin_family must be initialized to the address family of the socket, passed by sd. If sin->sin_port is ‘0’ then an anonymous port (in the range 600-1023) will be chosen, and if bind(2) is successful, the sin->sin_port will be updated to contain the allocated port.
If sin is the
NULL pointer, an anonymous port will be allocated
(as above). However, there is no way for
bindresvport()
to return the allocated port in this case.
Only root can bind to a privileged port; this call will fail for any other users.
Function prototype of
bindresvport()
is biased to AF_INET socket. The
bindresvport_sa()
function acts exactly the same, with more neutral function prototype. Note
that both functions behave exactly the same, and both support
AF_INET6 sockets as well as
AF_INET sockets.
The bindresvport() function returns the
value 0 if successful; otherwise the value -1 is returned and
the global variable errno is set to indicate the
error.
EPFNOSUPPORT]The bindresvport() function may also fail
and set errno for any of the errors specified for the
calls bind(2), getsockopt(2), or
setsockopt(2).
| November 22, 1987 | Mac OS X 12 |