Name
t_sync - synchronize transport library
Syntax
#include <tiuser.h>
int t_sync(fd)
int fd;
Description
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 a raw file descriptor
[obtained via open(S), dup(S), or as a result of a fork(S)
and exec(S)] 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 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 provider. t_sync 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 t_sync is issued.
If the provider is undergoing a state transition when t_sync
is called, the function will fail.
On failure, t_errno may be set to one of the following:
[TBADF] The specified file descriptor is a valid
open file descriptor but 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(S), exec(S), fork(S), open(S) in the XENIX Reference.
Network Programmer's Guide.
Diagnostics
The t_sync function returns the state of the transport
provider on successful completion and -1 on failure, and
t_errno is set to indicate the error. The state returned
may be one of the following:
T_UNBND unbound
T_IDLE idle
T_OUTCON outgoing connection pending
T_INCON incoming connection pending
T_DATAXFER data transfer
T_OUTREL outgoing orderly release (waiting for an
orderly release indication)
T_INREL incoming orderly release (waiting for an
orderly release request).
Standards Conformance
t_sync is conformant with:
AT&T SVID Issue 2, Select Code 307-127.
(printed 6/18/89)