NAME

connect − initiate a connection on a socket

SYNOPSIS

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>                    /∗ for Unix domain only ∗/
#include <netinet/in.h>                /∗ for Internet domain only ∗/

int connect (s, name, namelen)
int s;
struct sockaddr ∗name;
int namelen;

DESCRIPTION

The parameter s is a socket.  If it is of type SOCK_DGRAM, then this call permanently specifies the peer to which datagrams are to be sent; if it is of type SOCK_STREAM, then 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.  Each communications space interprets the name parameter in its own way. 

RETURN VALUE

If the connection or binding succeeds, then 0 is returned.  Otherwise a −1 is returned, and a more specific error code is stored in errno. 

ERRORS

The 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. 

[EAGAIN] The socket is non-blocking and the and the connection cannot be completed immediately.  It is possible to select(2) the socket while it is connecting by selecting it for writing. 

[EINVAL] Invalid system call argument (probably namelen). 

[EACCES] The attempt to connect failed because of the mandatory access control enforced on a CX/SX system (B1 only).  The security level of the connecting process must be the same as the accepting process for SOCK_STREAM sockets.  The security level of the connecting process must dominate the peer’s for SOCK_DGRAM sockets.  The security level of the connecting process must also be within the security clearance of the network interface used by Internet domain sockets.  This error is also returned on a CX/SX (B1 or C2) system when a process does not have write access to the file associated with a bound UX domain socket. 

NOTE

This call is defined in the 88open Binary and Object Compatibility Standards’ Networking Supplements (BCSNS and OCSNS) for use in BCS/OCS compliant networking applications.  OCS/OCSNS-defined functions may be accessed by passing OCS options to cc(1) and ld(1). 

SEE ALSO

accept(2), select(2), socket(2), getsockname(2).  See also bind(2) for address formats in different communication domains. 

CX/UX Programmer’s Reference Manual