t_sndudata(3N)                   DG/UX 5.4.2                  t_sndudata(3N)


NAME
       tsndudata - send a data unit

SYNOPSIS
       #include <tiuser.h>

       int tsndudata (int fd, struct tunitdata *unitdata);

DESCRIPTION
       This function is used in connectionless mode to send a data unit to
       another transport user.  fd identifies the local transport endpoint
       through which data will be sent, and unitdata points to a tunitdata
       structure containing the following members:

              struct netbuf addr;
              struct netbuf opt;
              struct netbuf udata;

       netbuf is described in intro(3).  In unitdata, addr specifies the
       protocol address of the destination user, opt identifies protocol-
       specific options that the user wants associated with this request,
       and udata specifies the user data to be sent.  The user may choose
       not to specify what protocol options are associated with the transfer
       by setting the len field of opt to zero.  In this case, the provider
       may use default options.

       If the len field of udata is zero, and the sending of zero bytes is
       not supported by the underlying transport provider, tsndudata will
       return -1 with terrno set to TBADDATA.

       By default, tsndudata operates in synchronous mode and may wait if
       flow control restrictions prevent the data from being accepted by the
       local transport provider at the time the call is made.  However, if
       ONDELAY or ONONBLOCK is set (via topen or fcntl), tsndudata will
       execute in asynchronous mode and will fail under such conditions.

       If tsndudata is issued from an invalid state, or if the amount of
       data specified in udata exceeds the TSDU size as returned in the tsdu
       field of the info argument of topen or tgetinfo, the provider will
       generate an EPROTO protocol error.  (See TSYSERR below.)  If the
       state is invalid, this error may not occur until a subsequent
       reference is made to the transport endpoint.

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

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

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

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



Licensed material--property of copyright holder(s)                         1

t_sndudata(3N)                   DG/UX 5.4.2                  t_sndudata(3N)


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

       [TBADDATA]        nbytes is zero and sending zero bytes is not
                         supported by the transport provider.

SEE ALSO
       intro(3), trcvudata(3N), trcvuderr(3N).
       UNIX System V Network Programmer's Guide.

DIAGNOSTICS
       tsndudata returns 0 on successful completion and -1 on failure
       terrno is set to indicate the error.












































Licensed material--property of copyright holder(s)                         2