t_optmgmt(3N)                  DG/UX R4.11MU05                 t_optmgmt(3N)


NAME
       toptmgmt - manage options for a transport endpoint

SYNOPSIS
       #include <tiuser.h>

       int toptmgmt (int fd, struct toptmgmt *req, struct toptmgmt *ret);

DESCRIPTION
       The toptmgmt function enables a transport user to retrieve, verify,
       or negotiate protocol options with the transport provider.  fd
       identifies a bound transport endpoint.

       The req and ret arguments point to a toptmgmt structure containing
       the following members:

              struct netbuf opt;
              long flags;

       The opt field identifies protocol options and the flags field is used
       to specify the action to take with those options.

       The options are represented by a netbuf [see intro(3); also for len,
       buf, and maxlen] structure in a manner similar to the address in
       tbind.  req is used to request a specific action of the provider and
       to send options to the provider.  len specifies the number of bytes
       in the options, buf points to the options buffer, and maxlen has no
       meaning for the req argument.  The transport provider may return
       options and flag values to the user through ret.  For ret, maxlen
       specifies the maximum size of the options buffer and buf points to
       the buffer where the options are to be placed.  On return, len
       specifies the number of bytes of options returned.  maxlen has no
       meaning for the req argument, but must be set in the ret argument to
       specify the maximum number of bytes the options buffer can hold.  The
       actual structure and content of the options is imposed by the
       transport provider.

       The flags field of req can specify one of the following actions:

       TNEGOTIATE    This action enables the user to negotiate the values
                      of the options specified in req with the transport
                      provider.  The provider will evaluate the requested
                      options and negotiate the values, returning the
                      negotiated values through ret.

       TCHECK        This action enables the user to verify whether the
                      options specified in req are supported by the
                      transport provider.  On return, the flags field of ret
                      will have either TSUCCESS or TFAILURE set to
                      indicate to the user whether the options are
                      supported.  These flags are only meaningful for the
                      TCHECK request.

       TDEFAULT      This action enables a user to retrieve the default
                      options supported by the transport provider into the
                      opt field of ret.  In req, the len field of opt must
                      be zero and the buf field may be NULL.

       If issued as part of the connectionless-mode service, toptmgmt may
       block due to flow control constraints.  The function will not
       complete until the transport provider has processed all previously
       sent data units.

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

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

       [TOUTSTATE]         The function was issued in the wrong sequence.

       [TACCES]            The user does not have permission to negotiate
                           the specified options.

       [TBADOPT]           The specified protocol options were in an
                           incorrect format or contained illegal
                           information.

       [TBADFLAG]          An invalid flag was specified.

       [TBUFOVFLW]         The number of bytes allowed for an incoming
                           argument is not sufficient to store the value of
                           that argument.  The information to be returned in
                           ret will be discarded.

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

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

DIAGNOSTICS
       toptmgmt returns 0 on success and -1 on failure and terrno is set
       to indicate the error.


Licensed material--property of copyright holder(s)