Man

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CONNECTAT(2)              FreeBSD System Calls Manual             CONNECTAT(2)

NAME
     connectat - initiate a connection on a socket

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/types.h>
     #include <sys/socket.h>

     #include <fcntl.h>

     int
     connectat(int fd, int s, const struct sockaddr *name, socklen_t namelen);

DESCRIPTION
     The connectat() system call initiates a connection on a socket.  It works
     just like the connect(2) system call with two exceptions:

           1.   It is limited to sockets in the PF_LOCAL domain.

           2.   If the file path stored in the sun_path field of the
                sockaddr_un structure is a relative path, it is located
                relative to the directory associated with the file descriptor
                fd.  If connectat() is passed the special value AT_FDCWD in
                the fd parameter, the current working directory is used and
                the behavior is identical to a call to connect(2).

RETURN VALUES
     The connectat() 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
     The connectat() system call may fail with the same errors as the
     connect(2) system call for a UNIX domain socket or with the following
     errors:

     [EBADF]            The sun_path field does not specify an absolute path
                        and the fd argument is neither AT_FDCWD nor a valid
                        file descriptor.

     [ENOTDIR]          The sun_path field is not an absolute path and fd is
                        neither AT_FDCWD nor a file descriptor associated with
                        a directory.

SEE ALSO
     bindat(2), connect(2), socket(2), unix(4)

AUTHORS
     The connectat was developed by Pawel Jakub Dawidek <[email protected]>
     under sponsorship from the FreeBSD Foundation.

FreeBSD 11.1-RELEASE-p4        February 13, 2013       FreeBSD 11.1-RELEASE-p4
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