This routine is part of the XTI interfaces which evolved from the TLI interfaces. XTI represents the future evolution of these interfaces. However, TLI interfaces are
supported for compatibility. When using a TLI routine that has the same name as an XTI routine, the tiuser.h header file must be used. Refer to the TLI COMPATIBILITY section for
a description of differences between the two interfaces.
For the transport endpoint specified by fd, t_sync() synchronizes the data structures managed by the transport library with information from the underlying transport provider. In doing so, it can convert an uninitialized file descriptor (obtained by
means of a open(2), dup(2)
or as a result of a fork(2) and exec(2))
to an initialized transport endpoint, assuming that the file descriptor referenced a transport endpoint, by updating and allocating the necessary library data structures. 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(2), the new process must issue a t_sync() 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 transport endpoint. The function t_sync()
returns the current state of the transport endpoint 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 endpoint's state after a t_sync() is issued.
If the transport endpoint is undergoing a state transition when t_sync() is called, the function will fail.
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