Retrieves a socket with a privileged address.
int rresvport_af(int *port, int family);
The rresvport_af subroutine obtains a socket with a privileged address bound to the socket. A privileged Internet port is one that falls in a range between 0 and 1023.
This subroutine is similar to the existing rresvport() subroutine, except that rresvport_af also takes and address family as an argument. This function is capable of creating either an AF_INET/TCP or an AF_INET6/TCP socket.
Only processes with an effective user ID of root user can use the rresvport subroutine. An authentication scheme based on remote port numbers is used to verify permissions.
If the connection succeeds, a socket in the Internet domain of type SOCK_STREAM is returned to the calling process.
All applications containing the rresvport subroutine must be compiled with the _BSD macro set to a specific value. Acceptable values are 43 and 44. In addition, all socket applications must include the BSD libbsd.a library.
Item | Description |
---|---|
port | Specifies the port to use for the connection. |
family | Specifies either AF_INET or AF_INET6 to accommodate the appropriate version. |
Upon successful completion, the rresvport_af subroutine returns a valid, bound socket descriptor.
Item | Description |
---|---|
EAFNOSUPPORT | The address family is not supported. |
EAGAIN | All network ports are in use. |
EMFILE | Two hundred file descriptors are currently open. |
ENFILE | The system file table is full. |
ENOBUFS | Insufficient buffers are available in the system to complete the subroutine. |
Item | Description |
---|---|
/etc/services | Contains the service names. |