t_sync(3N)            (Networking Support Utilities)             t_sync(3N)


   NAME
         tsync - synchronize transport library

   SYNOPSIS
         #include <tiuser.h>

         int tsync (int fd);

   DESCRIPTION
         For the transport endpoint specified by fd, tsync synchronizes the
         data structures managed by the transport library with information
         from the underlying transport provider.  In doing so, it can convert
         a raw file descriptor [obtained via open(2), dup(2), or as a result
         of a fork(2) and exec(2)] to an initialized transport endpoint,
         assuming that file descriptor referenced a transport provider.  This
         function also allows two cooperating processes to synchronize their
         interaction with a transport provider.

         For example, if a process forks a new process and issues an exec, the
         new process must issue a tsync to build the private library data
         structure associated with a transport endpoint and to synchronize the
         data structure with the relevant provider information.

         It is important to remember that the transport provider treats all
         users of a transport endpoint as a single user.  If multiple
         processes are using the same endpoint, they should coordinate their
         activities so as not to violate the state of the provider.  tsync
         returns the current state of the provider to the user, thereby
         enabling the user to verify the state before taking further action.
         This coordination is only valid among cooperating processes; it is
         possible that a process or an incoming event could change the
         provider's state after a tsync is issued.

         If the provider is undergoing a state transition when tsync is
         called, the function will fail.

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

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

         [TSTATECHNG]       The transport provider is undergoing a state
                            change.

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

   SEE ALSO
         dup(2), exec(2), fork(2), open(2).
         Programmer's Guide: Networking Interfaces.



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   t_sync(3N)            (Networking Support Utilities)             t_sync(3N)


   DIAGNOSTICS
         tsync returns the state of the transport provider on successful
         completion and -1 on failure and terrno is set to indicate the
         error.  The state returned may be one of the following:

         TUNBND            unbound

         TIDLE             idle

         TOUTCON           outgoing connection pending

         TINCON            incoming connection pending

         TDATAXFER         data transfer

         TOUTREL           outgoing orderly release (waiting for an orderly
                            release indication)

         TINREL            incoming orderly release (waiting for an orderly
                            release request)

































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