t_bind(3N) t_bind(3N)
NAME
tbind - bind an address to a transport endpoint
SYNOPSIS
#include <sys/tiuser.h>
int tbind (int fd, struct tbind *req, struct tbind *ret);
DESCRIPTION
This function associates a protocol address with the transport end-
point specified by fd and activates that transport endpoint. In con-
nection mode, the transport provider may begin accepting or requesting
connections on the transport endpoint. In connectionless mode, the
transport user may send or receive data units through the transport
endpoint.
The req and ret arguments point to a tbind structure containing the
following members:
struct netbuf addr;
unsigned qlen;
The addr field of the tbind structure specifies a protocol address
and the qlen field is used to indicate the maximum number of outstand-
ing connect indications.
req is used to request that an address, represented by the netbuf
structure, be bound to the given transport endpoint. len specifies the
number of bytes in the address and buf points to the address buffer.
maxlen has no meaning for the req argument. On return, ret contains
the address that the transport provider actually bound to the trans-
port endpoint; this may be different from the address specified by the
user in req. In ret, the user specifies maxlen, which is the maximum
size of the address buffer, and buf, which points to the buffer where
the address is to be placed. On return, len specifies the number of
bytes in the bound address and buf points to the bound address. If
maxlen is not large enough to hold the returned address, an error will
result.
If the requested address is not available, or if no address is speci-
fied in req (the len field of addr in req is zero) the transport pro-
vider may assign an appropriate address to be bound, and will return
that address in the addr field of ret. The user can compare the
addresses in req and ret to determine whether the transport provider
bound the transport endpoint to a different address than that
requested.
req may be NULL if the user does not wish to specify an address to be
bound. Here, the value of qlen is assumed to be zero, and the trans-
port provider must assign an address to the transport endpoint. Simi-
larly, ret may be NULL if the user does not care what address was
bound by the provider and is not interested in the negotiated value of
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t_bind(3N) t_bind(3N)
qlen. It is valid to set req and ret to NULL for the same call, in
which case the provider chooses the address to bind to the transport
endpoint and does not return that information to the user.
The qlen field has meaning only when initializing a connection-mode
service. It specifies the number of outstanding connect indications
the transport provider should support for the given transport end-
point. An outstanding connect indication is one that has been passed
to the transport user by the transport provider. A value of qlen
greater than zero is only meaningful when issued by a passive trans-
port user that expects other users to call it. The value of qlen will
be negotiated by the transport provider and may be changed if the
transport provider cannot support the specified number of outstanding
connect indications. On return, the qlen field in ret will contain the
negotiated value.
This function allows more than one transport endpoint to be bound to
the same protocol address (however, the transport provider must sup-
port this capability also), but it is not allowable to bind more than
one protocol address to the same transport endpoint. If a user binds
more than one transport endpoint to the same protocol address, only
one endpoint can be used to listen for connect indications associated
with that protocol address. In other words, only one tbind for a
given protocol address may specify a value of qlen greater than zero.
In this way, the transport provider can identify which transport end-
point should be notified of an incoming connect indication. If a user
attempts to bind a protocol address to a second transport endpoint
with a value of qlen greater than zero, the transport provider will
assign another address to be bound to that endpoint. If a user accepts
a connection on the transport endpoint that is being used as the
listening endpoint, the bound protocol address will be found to be
busy for the duration of that connection. No other transport endpoints
may be bound for listening while that initial listening endpoint is in
the data transfer phase. This will prevent more than one transport
endpoint bound to the same protocol address from accepting connect
indications.
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.
TBADADDR The specified protocol address was in an incorrect
format or contained illegal information.
TNOADDR The transport provider could not allocate an address.
TACCES The user does not have permission to use the specified
address.
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t_bind(3N) t_bind(3N)
TBUFOVFLW The number of bytes allowed for an incoming argument
is not sufficient to store the value of that argument.
The provider's state will change to TIDLE and the
information to be returned in ret will be discarded.
TSYSERR A system error has occurred during execution of this
function.
DIAGNOSTICS
tbind returns 0 on success and -1 on failure and terrno is set to
indicate the error.
SEE ALSO
topen(3N), toptmgmt(3N), tunbind(3N).
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