#include <tiuser.h>
int t_connect(fd, sndcall, rcvcall) int fd; struct t_call *sndcall; struct t_call *rcvcall;
t_connect() enables a transport user to request a connection to the specified destination transport user. fd identifies the local transport endpoint where communication will be established, while sndcall and rcvcall point to a t_call() structure which contains the following members:
struct netbuf addr; struct netbuf opt; struct netbuf udata; int sequence;
The maxlen, len, and buf members of the netbuf structure are described in t_accept.3n In sndcall, addr specifies the protocol address of the destination transport user, opt presents any protocol-specific information that might be needed by the transport provider, udata points to optional user data that may be passed to the destination transport user during connection establishment, and sequence has no meaning for this function.
On return in rcvcall, addr returns the protocol address associated with the responding transport endpoint, opt presents any protocol-specific information associated with the connection, udata points to optional user data that may be returned by the destination transport user during connection establishment, and sequence has no meaning for this function.
opt implies no structure on the options that may be passed to the transport provider. The transport provider is free to specify the structure of any options passed to it. These options are specific to the underlying protocol of the transport provider. The user may choose not to negotiate protocol options by setting the len field of opt to 0. In this case, the transport provider may use default options.
udata enables the caller to pass user data to the destination transport user and receive user data from the destination user during connection establishment. However, the amount of user data must not exceed the limits supported by the transport provider as returned by t_open.3n or t_getinfo.3n If the len field of udata is 0 in sndcall, no data will be sent to the destination transport user.
On return, the addr, opt, and udata fields of rcvcall will be updated to reflect values associated with the connection. Thus, the maxlen field of each argument must be set before issuing this function to indicate the maximum size of the buffer for each. However, rcvcall may be NULL in which case no information is given to the user on return from t_connect().
By default,
t_connect()
executes in synchronous mode, and will wait for the destination
user's response before returning control to the local user.
A successful return (a return value of 0) indicates that the
requested connection has been established.
However, if
T_NDELAY
is set (using
t_open()
or
fcntl),
t_connect()
executes in asynchronous mode.
In this case, the call will not wait for the remote user's
response, but will return control immediately to the local user
and return -1 with
t_errno
set to
TNODATA
to indicate that the connection has not yet been established.
In this way, the function simply initiates the connection
establishment procedure by sending a connect request to the
destination transport user.
t_connect() returns:
[a manual with the abbreviation NETP]
Created by unroff & hp-tools. © somebody (See intro for details). All Rights Reserved. Last modified 11/5/97