NAME

t_accept − accept a connect request

SYNOPSIS

#include <tiuser.h>

int t_accept( int fd, int resfd, struct t_call ∗call);

DESCRIPTION

This function is issued by a transport user to accept a connect request.  fd identifies the local transport endpoint where the connect indication arrived, resfd specifies the local transport endpoint where the connection is to be established, and call contains information required by the transport provider to complete the connection.  call points to a t_call structure that contains the following members:

struct netbuf addr;
struct netbuf opt;
struct netbuf udata;
int sequence;

netbuf is described in intro(3N).  In call, addr is the address of the caller, opt indicates any protocol-specific parameters associated with the connection, udata points to any user data to be returned to the caller, and sequence is the value returned by t_listen that uniquely associates the response with a previously received connect indication. 

A transport user may accept a connection on either the same, or on a different, local transport endpoint from the one on which the connect indication arrived.  If the same endpoint is specified (that is, resfd=fd), the connection can be accepted unless the following condition is true: The user has received other indications on that endpoint but has not responded to them (with t_accept or t_snddis).  For this condition, t_accept will fail and set t_errno to TBADF. 

If a different transport endpoint is specified (resfd!=fd), the endpoint must be bound to a protocol address and must be in the T_IDLE state [see t_getstate(3N)] before the t_accept is issued. 

For both types of endpoints, t_accept will fail and set t_errno to TLOOK if there are indications (for example, a connect or disconnect) waiting to be received on that endpoint. 

The values of parameters specified by opt and the syntax of those values are protocol specific.  The udata argument enables the called transport user to send user data to the caller and the amount of user data must not exceed the limits supported by the transport provider as returned in the connect field of the info argument of t_open or t_getinfo.  If the len [see netbuf in intro(3N)] field of udata is zero, no data will be sent to the caller. 

On failure, t_errno may be set to one of the following:

TBADF The specified file descriptor does not refer to a transport endpoint, or the user is invalidly accepting a connection on the same transport endpoint on which the connect indication arrived. 

TOUTSTATE The function was issued in the wrong sequence on the transport endpoint referenced by fd, or the transport endpoint referred to by resfd is not in the T_IDLE state. 

TACCES The user does not have permission to accept a connection on the responding transport endpoint or use the specified options. 

TBADOPT The specified options were in an incorrect format or contained invalid information. 

TBADDATA The amount of user data specified was not within the bounds supported by the transport provider as returned in the connect field of the info argument of t_open or t_getinfo. 

TBADSEQ An invalid sequence number was specified. 

TLOOK An asynchronous event has occurred on the transport endpoint referenced by fd and requires immediate attention. 

TNOTSUPPORT This function is not supported by the underlying transport provider. 

TSYSERR A system error has occurred during execution of this function. 

SEE ALSO

intro(3N), t_connect(3N), t_getstate(3N), t_listen(3N), t_open(3N), t_rcvconnect(3N). 

DIAGNOSTICS

Upon successful completion, a value of 0 is returned.  Otherwise, a value of −1 is returned and t_errno is set to indicate the error. 

  —  Networking Support Utilities