t_optmgmt(3N)     UNIX System V(Networking Support Utilities)     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(3N); 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.




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t_optmgmt(3N)     UNIX System V(Networking Support Utilities)     t_optmgmt(3N)


      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(3N), tgetinfo(3N), topen(3N)
      Programmer's Guide:  Networking Interfaces

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















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