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instance method

Socket#connect

(::String | ::Addrinfo remote_sockaddr) -> ::Integer

socket.connect(remote_sockaddr) => 0

static VALUE
sock_connect(VALUE self, VALUE addr)
{
    VALUE rai;

    SockAddrStringValueWithAddrinfo(addr, rai);
    addr = rb_str_new4(addr);

    int result = rsock_connect(self, (struct sockaddr*)RSTRING_PTR(addr), RSTRING_SOCKLEN(addr), 0, RUBY_IO_TIMEOUT_DEFAULT);

    if (result < 0) {
        rsock_sys_fail_raddrinfo_or_sockaddr("connect(2)", addr, rai);
    }

    return INT2FIX(result);
}

Requests a connection to be made on the given remote_sockaddr. Returns 0 if successful, otherwise an exception is raised.

Parameter

remote_sockaddr - the struct sockaddr contained in a string or Addrinfo object

Example:

Example

# Pull down Google's web page
require 'socket'
include Socket::Constants
socket = Socket.new( AF_INET, SOCK_STREAM, 0 )
sockaddr = Socket.pack_sockaddr_in( 80, 'www.google.com' )
socket.connect( sockaddr )
socket.write( "GET / HTTP/1.0\r\n\r\n" )
results = socket.read

Unix-based Exceptions

On unix-based systems the following system exceptions may be raised if the call to connect fails:

Errno::EACCES - search permission is denied for a component of the prefix path or write access to the socket is denied
Errno::EADDRINUSE - the sockaddr is already in use
Errno::EADDRNOTAVAIL - the specified sockaddr is not available from the local machine
Errno::EAFNOSUPPORT - the specified sockaddr is not a valid address for the address family of the specified socket
Errno::EALREADY - a connection is already in progress for the specified socket
Errno::EBADF - the socket is not a valid file descriptor
Errno::ECONNREFUSED - the target sockaddr was not listening for connections refused the connection request
Errno::ECONNRESET - the remote host reset the connection request
Errno::EFAULT - the sockaddr cannot be accessed
Errno::EHOSTUNREACH - the destination host cannot be reached (probably because the host is down or a remote router cannot reach it)
Errno::EINPROGRESS - the O_NONBLOCK is set for the socket and the connection cannot be immediately established; the connection will be established asynchronously
Errno::EINTR - the attempt to establish the connection was interrupted by delivery of a signal that was caught; the connection will be established asynchronously
Errno::EISCONN - the specified socket is already connected
Errno::EINVAL - the address length used for the sockaddr is not a valid length for the address family or there is an invalid family in sockaddr
Errno::ENAMETOOLONG - the pathname resolved had a length which exceeded PATH_MAX
Errno::ENETDOWN - the local interface used to reach the destination is down
Errno::ENETUNREACH - no route to the network is present
Errno::ENOBUFS - no buffer space is available
Errno::ENOSR - there were insufficient STREAMS resources available to complete the operation
Errno::ENOTSOCK - the socket argument does not refer to a socket
Errno::EOPNOTSUPP - the calling socket is listening and cannot be connected
Errno::EPROTOTYPE - the sockaddr has a different type than the socket bound to the specified peer address
Errno::ETIMEDOUT - the attempt to connect timed out before a connection was made.

On unix-based systems if the address family of the calling socket is AF_UNIX the follow exceptions may be raised if the call to connect fails:

Errno::EIO - an i/o error occurred while reading from or writing to the file system
Errno::ELOOP - too many symbolic links were encountered in translating the pathname in sockaddr
Errno::ENAMETOOLLONG - a component of a pathname exceeded NAME_MAX characters, or an entire pathname exceeded PATH_MAX characters
Errno::ENOENT - a component of the pathname does not name an existing file or the pathname is an empty string
Errno::ENOTDIR - a component of the path prefix of the pathname in sockaddr is not a directory

Windows Exceptions

On Windows systems the following system exceptions may be raised if the call to connect fails:

Errno::ENETDOWN - the network is down
Errno::EADDRINUSE - the socket’s local address is already in use
Errno::EINTR - the socket was cancelled
Errno::EINPROGRESS - a blocking socket is in progress or the service provider is still processing a callback function. Or a nonblocking connect call is in progress on the socket.
Errno::EALREADY - see Errno::EINVAL
Errno::EADDRNOTAVAIL - the remote address is not a valid address, such as ADDR_ANY TODO check ADDRANY TO INADDR_ANY
Errno::EAFNOSUPPORT - addresses in the specified family cannot be used with with this socket
Errno::ECONNREFUSED - the target sockaddr was not listening for connections refused the connection request
Errno::EFAULT - the socket’s internal address or address length parameter is too small or is not a valid part of the user space address
Errno::EINVAL - the socket is a listening socket
Errno::EISCONN - the socket is already connected
Errno::ENETUNREACH - the network cannot be reached from this host at this time
Errno::EHOSTUNREACH - no route to the network is present
Errno::ENOBUFS - no buffer space is available
Errno::ENOTSOCK - the socket argument does not refer to a socket
Errno::ETIMEDOUT - the attempt to connect timed out before a connection was made.
Errno::EWOULDBLOCK - the socket is marked as nonblocking and the connection cannot be completed immediately
Errno::EACCES - the attempt to connect the datagram socket to the broadcast address failed

See

connect manual pages on unix-based systems
connect function in Microsoft’s Winsock functions reference

See also #bind #connect_nonblock #accept_nonblock #ipv6only! also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

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