hpux man page for t_snd

t_snd(3)						     Library Functions Manual							  t_snd(3)

NAME
       t_snd() - send data or expedited data over a connection

SYNOPSIS
DESCRIPTION
       This  function is used to send either normal or expedited data.	fd identifies the local transport endpoint over which data should be sent,
       buf points to the user data, nbytes specifies the number of bytes of user data to be sent, and flags specifies any optional flags described
       below:

       if set in	flags, the data will be sent as expedited data and will be subject to the interpretations of the transport provider.

       if set in	flags, this indicates to the transport provider that the transport service data unit, TSDU (or expedited transport service
			data unit - ETSDU), is being sent through multiple calls.  Each with the flag set indicates that another will follow  with
			more  data  for  the  current TSDU.  The end of the TSDU (or ETSDU) is identified by a call with the flag not set.  Use of
			enables a user to break up large logical data units without losing the boundaries of those units at the other end  of  the
			connection.   The  flag implies nothing about how the data is packaged for transfer below the transport interface.  If the
			transport provider does not support the concept of a TSDU as indicated in the info argument on return from or the flag	is
			not meaningful and should be ignored.

       The  sending of a zero-length fragment of a TSDU or ETSDU is only permitted where this is used to indicate the end of a TSDU or ETSDU, i.e.
       when the flag is not set.  Some transport providers also forbid zero-length TSDUs and ETSDUs.

       By default, operates in synchronous mode and may wait if flow control restrictions prevent the data from being accepted by the local trans-
       port  provider  at  the	time the call is made.	However, if is set (via or will execute in asynchronous mode, and will fail immediately if
       there are flow control restrictions.  For XTI only, the process can arrange to be informed when the flow control restrictions  are  cleared
       via

       will wait if STREAMS internal resources are not available, even if is set.  non-blocking behavior applies only to flow control conditions.

       On  successful completion, returns the number of bytes accepted by the transport provider.  In synchronous mode, this will equal the number
       of bytes specified in nbytes.  However, if (asynchronous mode) is set, it is possible that only part of the data will actually be  accepted
       by  the transport provider.  In this case, will set for the data that can be accepted by the provider, and return a value that is less than
       the value of nbytes.

       If nbytes is zero and sending of zero octets is not supported by the underlying transport service, will return -1 with set to [TBADDATA].

       The size of each TSDU or ETSDU must not exceed the limits of the transport provider as returned in the TSDU or ETSDU  fields  of  the  info
       argument of or Failure to comply will result in a protocol error. (See [TSYSERR] below.)

       For XTI only, the error [TLOOK] may be returned to inform the process that an event (e.g., a disconnect) has occurred.

       For TLI only, if the transport endpoint is in any state but or the transport provider will set to [TSYSERR] and set the system to [EPROTO].

   Caveats
       It  is  important to remember that the transport provider treats all users of a transport endpoint as a single user.  Therefore, if several
       processes issue concurrent calls then the different data may be intermixed.

       Multiple sends which exceed the maximum TSDU or ETSDU size may not be discovered by XTI.  In this case, an  implementation-dependent  error
       will  result  (generated  by the transport provider) perhaps on a subsequent XTI call.  This error may take the form of a connection abort,
       [TSYSERR], [TBADDATA], or a [TPROTO].

       If multiple sends which exceed the maximum TSDU or ETSDU size are detected by XTI, fails with [TBADDATA].

   Fork Safety
       is not fork-safe.

RETURN VALUE
       On successful completion, returns the number of bytes accepted by the transport provider. Otherwise, -1 is returned on failure and  is  set
       to indicate the error.

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

       [TBADF]		   The specified identifier does not refer to a transport endpoint.

       [TBADDATA]	   Illegal amount of data:

			   A  single send was attempted specifying a TSDU (ETSDU) or fragment TSDU (ETSDU) greater than that specified by the cur-
			   rent values of the TSDU or ETSDU fields in the info argument.

			   A send of zero byte TSDU (ETSDU) or zero byte fragment of TSDU (ETSDU) is not supported by the provider.

			   Multiple sends were attempted resulting in a TSDU (ETSDU) larger than that specified by the current value of  the  TSDU
			   or ETSDU fields in the info argument. The ability of XTI to catch such an error case is implementation-dependent.

       [TBADFLAG]	   An invalid flag was specified.

       [TFLOW]		   was set, but the flow control mechanism prevented the transport provider from accepting all or part of the data at this
			   time.

       [TLOOK]		   An asynchronous event has occurred on this transport endpoint and requires immediate attention.

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

       [TOUTSTATE]	   The function was issued in the wrong sequence on the endpoint referenced by fd.

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

       [TPROTO] 	   (XTI only) This error indicates that a communication problem has been detected between XTI and the  transport  provider
			   for which there is no other suitable XTI (

SEE ALSO
       t_getinfo(3), t_open(3), t_rcv(3), thread_safety(5).

STANDARDS CONFORMANCE
																	  t_snd(3)