BINDRESVPORT(3) Linux Programmers Manual BINDRESVPORT(3)
bindresvport - bind a socket to a privileged IP port
int bindresvport(int sd, struct sockaddr_in **sin);
bindresvport() is used to bind a socket descriptor to a privileged IP
port, that is, a port number in the range 0-1023.
If in->sin_port is 0 then an anonymous port in the range 600 to 1023 be
chosen. If the bind(2) performed by bindresvport() is successful, 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, and an anonymous port is allocated (as above). However, in
this case, bindresvport() has no way to return the port number actually
bindresvport() returns 0 if it is successful, otherwise -1 is returned
and errno set to indicate the cause of the error.
bindresvport() can fail for any of the same reasons as bind(2).
Not in POSIX.1-2001. Present on the BSDs, Solaris, and many other sys
Only root can bind to a privileged port; this call will fail for any
other users. In addition, the following error may occur:
sin is not NULL and sin->sin_family is not AF_INET.
This page is part of release 3.05 of the Linux man-pages project. A
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