CONNECTAT(2) BSD 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 indi-
cate 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 <pawel@dawidek.net> under sponsorship from the FreeBSD Foundation.
BSD February 13, 2013 BSD
Check Out this Related Man Page
CONNECT(2) BSD System Calls Manual CONNECT(2)NAME
connect -- initiate a connection on a socket
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/socket.h>
int
connect(int s, const struct sockaddr *name, socklen_t namelen);
DESCRIPTION
The parameter s is a socket. If it is of type SOCK_DGRAM, this call specifies the peer with which the socket is to be associated; this
address is that to which datagrams are to be sent, and the only address from which datagrams are to be received. If the socket is of type
SOCK_STREAM, this call attempts to make a connection to another socket. The other socket is specified by name, which is an address in the
communications space of the socket. namelen indicates the amount of space pointed to by name, in bytes. Each communications space inter-
prets the name parameter in its own way. Generally, stream sockets may successfully connect() only once; datagram sockets may use connect()
multiple times to change their association. Datagram sockets may dissolve the association by connecting to an invalid address, such as a
null address.
If a connect() call is interrupted by a signal, it will return with errno set to EINTR and the connection attempt will proceed as if the
socket was non-blocking. Subsequent calls to connect() will set errno to EALREADY.
RETURN VALUES
If the connection or binding succeeds, 0 is returned. Otherwise a -1 is returned, and a more specific error code is stored in errno.
ERRORS
The connect() call fails if:
[EBADF] s is not a valid descriptor.
[ENOTSOCK] s is a descriptor for a file, not a socket.
[EADDRNOTAVAIL] The specified address is not available on this machine.
[EAFNOSUPPORT] Addresses in the specified address family cannot be used with this socket.
[EISCONN] The socket is already connected.
[ETIMEDOUT] Connection establishment timed out without establishing a connection.
[ECONNREFUSED] The attempt to connect was forcefully rejected.
[ENETUNREACH] The network isn't reachable from this host.
[EADDRINUSE] The address is already in use.
[EFAULT] The name parameter specifies an area outside the process address space.
[EINPROGRESS] The socket is non-blocking and the connection cannot be completed immediately. It is possible to select(2) or poll(2) for
completion by selecting or polling the socket for writing. The success or failure of the connect operation may be deter-
mined by using getsockopt(2) to read the socket error status with the SO_ERROR option at the SOL_SOCKET level. The
returned socket error status is zero on success, or one of the error codes listed here on failure.
[EALREADY] Either the socket is non-blocking mode or a previous call to connect() was interrupted by a signal, and the connection
attempt has not yet been completed.
[EINTR] The connection attempt was interrupted by a signal.
The following errors are specific to connecting names in the UNIX domain. These errors may not apply in future versions of the UNIX IPC
domain.
[ENOTDIR] A component of the path prefix is not a directory.
[ENAMETOOLONG] A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} characters.
[ENOENT] The named socket does not exist.
[EACCES] Search permission is denied for a component of the path prefix, or write access to the named socket is denied.
[ELOOP] Too many symbolic links were encountered in translating the pathname.
SEE ALSO accept(2), getsockname(2), getsockopt(2), poll(2), select(2), socket(2)HISTORY
The connect() function call appeared in 4.2BSD.
BSD May 18, 2004 BSD