t_look.3.man

This a separate release of the OpenSS7 X/Open XTI/TLI library, TLI modules (timod, tirdwr) and the I

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.\"
.\"
.\"
.\"
.TH T_LOOK 3 "2004/05/16 02:35:36" "strxnet-0_9_2-4" "OpenSS7 XTI/TLI Library"
.\"
.\"
.SH NAME
.B t_look
\- look for a transport event
.\"
.\"
.SH SYNOPSIS
.PP
.B #include <xti.h>
.HP 8
.BI "int t_look(int " fd );
.\"
.\"
.SH ARGUMENTS
.PP
.TP
.I fd
the transport endpoint upon which to look for events.
.\"
.\"
.SH DESCRIPTION
.PP
.BR t_look ()
looks for a pending asynchronous event on the local transport endpoint
specified by
.IR fd .
.PP
.I fd
specifies the local transport endpoint upon which to look for a pending
asynchronous event.
.\"
.\"
.SH CAVEATS
.PP
When an XTI/TLI library call is expecting a specific response from the transport
service provider, such as in
.BR t_accept (3),
.BR t_addleaf (3),
.BR t_connect (3),
.BR t_listen (3),
.BR t_rcv (3),
.BR t_rcvconnect (3),
.BR t_rcvleafchange (3),
.BR t_rcvrel (3),
.BR t_rcvreldata (3),
.BR t_rcvv (3),
.BR t_rcvvudata (3),
.BR t_removeleaf (3),
.BR t_snd (3),
.BR t_snddis (3),
.BR t_sndrel (3),
.BR t_sndreldata (3),
.BR t_sndudata (3),
.BR t_sndv (3),
.BR t_sndvudata (3),
and
.BR t_unbind (3),
an asynchronous event is received other than the expected event, the above
calls will fail, return -1 and set
.IR t_errno (3)
to
.BR TLOOK .
When such a failure occurs,
.BR t_look ()
can be used to determine which asynchronous event occured and determine the
next course of action.
.PP
Also,
.BR t_look ()
can be used to determine which event is pending without previoulsy calling one
of the XTI/TLI library calls listed above.  For example,
.BR t_look ()
can be called after a call to
.BR poll (2)
for a group of file descriptors to determine the event that has occured on the
transport endpoint.  This is in fitting with the
.BR poll (2)
example listed in XNS 5.2.
.[
xns
.]
.PP
The following XTI/TLI library commands return
.RB [ TLOOK ]
when the listed asynchronous events have occured:
.sp
.TS
tab(:);
lblssss.
t_accept\fR(3):T_DISCONNECT, T_LISTEN
t_connect\fR(3):T_DISCONNECT, T_LISTEN
t_listen\fR(3):T_DISCONNECT
t_rcv\fR(3):T_DISCONNECT, T_ORDREL
t_rcvconnect\fR(3):T_DISCONNECT
t_rcvrel\fR(3):T_DISCONNECT
t_rcvreldata\fR(3):T_DISCONNECT
t_rcvudata\fR(3):T_UDERR
t_rcvv\fR(3):T_DISCONNECT, T_ORDREL
t_rcvvudata\fR(3):T_UDERR
t_snd\fR(3):T_DISCONNECT, T_ORDREL
t_sndudata\fR(3):T_UDERR
t_sndv\fR(3):T_DISCONNECT, T_ORDREL
t_sndvudata\fR(3):T_UDERR
t_unbind\fR(3):T_LISTEN, T_DATA, T_UDERR
t_sndrel\fR(3):T_DISCONNECT
t_sndreldata\fR(3):T_DISCONNECT
t_snddis\fR(3):T_DISCONNECT
.TE
.\"
.\"
.SH "RETURN VALUE"
.PP
Upon success,
.BR t_look ()
returns a positive integer reflecting the asynchronous event received and is one of the
following values:
.TP
.B T_LISTEN
connection indication received.
.TP
.B T_CONNECT
connection confirmation received.
.TP
.B T_DATA
normal data received.
.TP
.B T_EXDATA
expedited data received.
.TP
.B T_DISCONNECT
disconnection received.
.TP
.B T_UDERR
datagram error indication received.
.TP
.B T_ORDREL
orderly release indication received.
.TP
.B T_GODATA
sending normal data is again possible.
.TP
.B T_GOEXDATA
sending expedited data is again possible.
.PP
Upon failure,
.BR t_look ()
returns -1 and sets
.IR t_errno (3)
to an appropriate error number.
.\"
.\"
.SH ERRORS
.PP
When
.BR t_look ()
fails, it returns -1 and sets
.IR t_errno (3)
to an appropriate error number as follows:
.TP \w'[TNOTSUPPORT]\(em'u
.RB [ TBADF ]
.I fd
is invalid.
.TP
.RB [ TPROTO ]
A protocol error occured between the XTI/TLI library and the underlying transport provider.
.TP
.RB [ TSYSERR ]
A \fBLinux\fR system error occured and the \fBLinux\fR error number is set in
.IR errno (3).
.\"
.\"
.SH "SEE ALSO"
.PP
.BR errno (3),
.BR t_accept (3),
.BR t_addleaf (3),
.BR t_connect (3),
.BR t_errno (3).
.BR t_listen (3),
.BR t_rcv (3),
.BR t_rcvconnect (3),
.BR t_rcvleafchange (3),
.BR t_rcvrel (3),
.BR t_rcvreldata (3),
.BR t_rcvv (3),
.BR t_rcvvudata (3),
.BR t_removeleaf (3),
.BR t_snd (3),
.BR t_snddis (3),
.BR t_sndrel (3),
.BR t_sndreldata (3),
.BR t_sndudata (3),
.BR t_sndv (3),
.BR t_sndvudata (3),
.BR t_unbind (3).
.\"
.\"
.SH "BUGS"
.PP
.BR t_look ()
has no known bugs.
.BR t_look ()
has been tested for the described behavior using the
.I /usr/bin/test-xnet
conformance test program.
.\"
.\"
.SH "CONFORMING TO"
.PP
XTI/TLI,
.[
XTI
.]
TPI,
.[
TPI Revision 2.0.0
.]
XPG5,
XNS 5.2,
.[
xns
.]
SUSv2.
.[
susv2
.]
.\"
.\"
.[
$LIST$
.]
.T4