te
Copyright 1994, The X/Open Company Ltd. All Rights Reserved Portions Copyright 1989 AT&T Portions Copyright (c) 1998, Sun Microsystems, Inc. All Rights Reserved
Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.
The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
This notice shall appear on any product containing this material.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
t_rcvv - receive data or expedited data sent over a connection and put the data into one or more non-contiguous buffers

#include <xti.h> 




int t_rcvv(int fd, struct t_iovec *iov, unsigned int iovcount, int *flags);

This function receives either normal or expedited data. The argument fd identifies the local transport endpoint through which data will arrive, iov points to an array of buffer address/buffer size pairs (iov_base, iov_len). The t_rcvv() function receives data into the buffers specified by iov0.iov_base, iov1.iov_base, through iov [iovcount-1].iov_base, always filling one buffer before proceeding to the next.

Note that the limit on the total number of bytes available in all buffers passed:

iov(0).iov_len + . . + iov(iovcount-1).iov_len)

may be constrained by implementation limits. If no other constraint applies, it will be limited by INT_MAX. In practice, the availability of memory to an application is likely to impose a lower limit on the amount of data that can be sent or received using scatter/gather functions.

The argument iovcount contains the number of buffers which is limited to T_IOV_MAX, which is an implementation-defined value of at least 16. If the limit is exceeded, the function will fail with TBADDATA.

The argument flags may be set on return from t_rcvv() and specifies optional flags as described below.

By default, t_rcvv() operates in synchronous mode and will wait for data to arrive if none is currently available. However, if O_NONBLOCK is set by means of t_open(3NSL) or fcntl(2), t_rcvv() will execute in asynchronous mode and will fail if no data is available. See TNODATA below.

On return from the call, if T_MORE is set in flags, this indicates that there is more data, and the current transport service data unit (TSDU) or expedited transport service data unit (ETSDU) must be received in multiple t_rcvv() or t_rcv(3NSL) calls. In the asynchronous mode, or under unusual conditions (for example, the arrival of a signal or T_EXDATA event), the T_MORE flag may be set on return from the t_rcvv() call even when the number of bytes received is less than the total size of all the receive buffers. Each t_rcvv() with the T_MORE flag set indicates that another t_rcvv() must follow to get more data for the current TSDU. The end of the TSDU is identified by the return of a t_rcvv() call with the T_MORE flag not set. If the transport provider does not support the concept of a TSDU as indicated in the info argument on return from t_open(3NSL) or t_getinfo(3NSL), the T_MORE flag is not meaningful and should be ignored. If the amount of buffer space passed in iov is greater than zero on the call to t_rcvv(), then t_rcvv() will return 0 only if the end of a TSDU is being returned to the user.

On return, the data is expedited if T_EXPEDITED is set in flags. If T_MORE is also set, it indicates that the number of expedited bytes exceeded nbytes, a signal has interrupted the call, or that an entire ETSDU was not available (only for transport protocols that support fragmentation of ETSDUs). The rest of the ETSDU will be returned by subsequent calls to t_rcvv() which will return with T_EXPEDITED set in flags. The end of the ETSDU is identified by the return of a t_rcvv() call with T_EXPEDITED set and T_MORE cleared. If the entire ETSDU is not available it is possible for normal data fragments to be returned between the initial and final fragments of an ETSDU.

If a signal arrives, t_rcvv() returns, giving the user any data currently available. If no data is available, t_rcvv() returns -1, sets t_errno to TSYSERR and errno to EINTR. If some data is available, t_rcvv() returns the number of bytes received and T_MORE is set in flags.

In synchronous mode, the only way for the user to be notified of the arrival of normal or expedited data is to issue this function or check for the T_DATA or T_EXDATA events using the t_look(3NSL) function. Additionally, the process can arrange to be notified via the EM interface.

On successful completion, t_rcvv() returns the number of bytes received. Otherwise, it returns -1 on failure and t_errno is set to indicate the error.

T_DATAXFER, T_OUTREL.

On failure, t_errno is set to one of the following:

TBADDATA

TBADF

TLOOK

TNODATA

TNOTSUPPORT

TOUTSTATE

TPROTO

TSYSERR

In the TLI interface definition, no counterpart of this routine was defined.

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
MT Level	Safe

fcntl(2), t_getinfo(3NSL), t_look(3NSL), t_open(3NSL), t_rcv(3NSL), t_snd(3NSL), t_sndv(3NSL), attributes(5)