CONNECT

Section: System Calls (2)
Index Return to Main Contents

BSD mandoc
BSD 4.2  

NAME

connect - initiate a connection on a socket  

SYNOPSIS

Fd #include <sys/types.h> Fd #include <sys/socket.h> Ft int Fn connect int s struct sockaddr *name int namelen  

DESCRIPTION

The parameter Fa 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 Fa name , which is an address in the communications space of the socket. Each communications space interprets the Fa name parameter in its own way. Generally, stream sockets may successfully Fn connect only once; datagram sockets may use Fn connect multiple times to change their association. Datagram sockets may dissolve the association by connecting to an invalid address, such as a null address.  

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 Fn connect call fails if:

Bq Er EBADF
Fa S is not a valid descriptor.
Bq Er ENOTSOCK
Fa S is a descriptor for a file, not a socket.
Bq Er EADDRNOTAVAIL
The specified address is not available on this machine.
Bq Er EAFNOSUPPORT
Addresses in the specified address family cannot be used with this socket.
Bq Er EISCONN
The socket is already connected.
Bq Er ETIMEDOUT
Connection establishment timed out without establishing a connection.
Bq Er ECONNREFUSED
The attempt to connect was forcefully rejected.
Bq Er ENETUNREACH
The network isn't reachable from this host.
Bq Er EADDRINUSE
The address is already in use.
Bq Er EFAULT
The Fa name parameter specifies an area outside the process address space.
Bq Er EINPROGRESS
The socket is non-blocking and the connection cannot be completed immediately. It is possible to select(2) for completion by selecting the socket for writing.
Bq Er EALREADY
The socket is non-blocking and a previous connection attempt has not yet been completed.

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.

Bq Er ENOTDIR
A component of the path prefix is not a directory.
Bq Er ENAMETOOLONG
A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} characters.
Bq Er ENOENT
The named socket does not exist.
Bq Er EACCES
Search permission is denied for a component of the path prefix.
Bq Er EACCES
Write access to the named socket is denied.
Bq Er ELOOP
Too many symbolic links were encountered in translating the pathname.

 

SEE ALSO

accept(2), select(2), socket(2), getsockname(2)  

HISTORY

The Fn connect function call appeared in BSD 4.2


 

Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUES
ERRORS
SEE ALSO
HISTORY

This document was created by man2html, using the manual pages.
Time: 16:28:59 GMT, April 18, 2022