home   contributing   bugs   download   online pages  

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | NOTES | SEE ALSO | COLOPHONThe Linux Programming Interface


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

NAME         top

       bindresvport - bind a socket to a privileged IP port

SYNOPSIS         top

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

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

DESCRIPTION         top

       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 allocated.

       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         top

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

ERRORS         top

       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         top

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

NOTES         top

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

SEE ALSO         top

       bind(2), getsockname(2)

COLOPHON         top

       This page is part of release 3.32 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)

HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface

customisable
counter