bindresvport(3) [suse man page]

BINDRESVPORT(3) 					     Linux Programmer's Manual						   BINDRESVPORT(3)

NAME

       bindresvport - bind a socket to a privileged IP port

SYNOPSIS

       #include <sys/types.h>
       #include <netinet/in.h>

       int bindresvport(int sockfd, struct sockaddr_in *sin);

DESCRIPTION

       bindresvport()  is used to bind a socket descriptor to a privileged anonymous IP port, that is, a port number arbitrarily selected from the
       range 512 to 1023.

       If the bind(2) performed by bindresvport() is successful, and sin is not NULL, then sin->sin_port returns the port  number  actually  allo-
       cated.

       sin  can  be  NULL,  in	which case sin->sin_family is implicitly taken to be AF_INET.  However, in this case, bindresvport() has no way to
       return the port number actually allocated.  (This information can later be obtained using getsockname(2).)

RETURN VALUE

       bindresvport() returns 0 on success; otherwise -1 is returned and errno set to indicate the cause of the error.

ERRORS

       bindresvport() can fail for any of the same reasons as bind(2).	In addition, the following errors may occur:

       EACCES The caller did not have superuser privilege (to be precise: the CAP_NET_BIND_SERVICE capability is required).

       EADDRINUSE
	      All privileged ports are in use.

       EAFNOSUPPORT (EPFNOSUPPORT in glibc 2.7 and earlier)
	      sin is not NULL and sin->sin_family is not AF_INET.

CONFORMING TO

       Not in POSIX.1-2001.  Present on the BSDs, Solaris, and many other systems.

NOTES

       Unlike some bindresvport() implementations, the glibc implementation ignores any value that the caller supplies in sin->sin_port.

SEE ALSO

       bind(2), getsockname(2)

COLOPHON

       This page is part of release 3.25 of the Linux man-pages project.  A description of the project, and information about reporting bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

								    2008-12-03							   BINDRESVPORT(3)

BINDRESVPORT(3) 					   BSD Library Functions Manual 					   BINDRESVPORT(3)

NAME

     bindresvport, bindresvport_sa -- bind a socket to a privileged IP port

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <sys/types.h>
     #include <rpc/rpc.h>

     int
     bindresvport(int sd, struct sockaddr_in *sin);

     int
     bindresvport_sa(int sd, struct sockaddr *sa);

DESCRIPTION

     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 allo-
     cated 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.

RETURN VALUES

     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.

ERRORS

     [EPFNOSUPPORT]	If second argument was supplied, and address family did not match between arguments.

     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).

SEE ALSO

     bind(2), getsockopt(2), setsockopt(2), ip(4)

BSD
								 November 22, 1987							       BSD