LassoScript Utility
Basics Browse Detail


Tag Link [Net->Wait] Category Networking
Type Member Source Available Yes
Support Preferred Version 7.0
Change Unchanged Data Source Any
Output Type Integer Security None
Implementation LCAPI Sets Lasso 8.5, Lasso 8.0, Lasso 7.0


The [Net->Wait] tag makes a [Net] object wait until data is ready for reading or writing. The tag takes two parameters. The first is a timeout period in seconds. The second specifies what condition the [Net->Wait] tag should wait for. The return value of the tag is either [Net_WaitRead], [Net_WaitWrite], or [Net_WaitTimeOut].

[Net_WaitRead] instructs [Net->Wait] to wait until there is data available for reading. [Net_WaitRead] will be returned as the value of the tag or [Net_WaitTimeOut] if the timeout period is reached before any data was made available for reading.

[Net_WaitWrite] instructs [Net->Wait] to wait until the connection can accept data for a write opertion. [Net_WaitWrite] will be returned as the value of the tag or [Net_WaitTimeOut] if the timeout period is reached before the connection became available for writing.

With no second parameter [Net->Wait] returns either [Net_WaitRead] or [Net_WaitWrite] depending on which state becomes available first. [Net_WaitTimeOut] is returned if the connection does not have data available for reading and is not avalable for writing before the timeout period is reached.


Variable: 'Connection' = (Net);
$Net->(Connect: '', '80');
If: ($Net->(Wait: 60, Net_WaitWrite) == Net_WaitWrite);
Output: 'Connection is ready for writing.';


Required Parameters
Time Out Period The time in seconds that the tag should wait before timing out.
Optional Parameters
Wait Type The optional condition that the tag should wait for. Either [Net_WaitRead] or [Net_WaitWrite].


To connect to a remote server using non-blocking TCP:

Use the [Net] type and its member tags to establish a TCP connection. The following example opens a non-blocking TCP connection to the Web server running on an example server and fetches the root document. The [Net->Wait] tag is used to wait until the connection is in the proper state for accepting data and until data is available for reading. The result will be an HTML page.

[Variable: 'myConnection' = (Net)]
[$myConnection->(SetBlocking: False)]
[Var: 'Result' = $myConnection->(Connect: '', 80)]
[Fail_If: $Result != Net_ConnectOK, (-1), 'TCP Error']
[Var: 'Result' = $myConnection->(Wait: 60, Net_WaitWrite)]
[Fail_If: $Result == Net_WaitTimeOut, (-1), 'TCP Timeout']
[Variable: 'Result' = $myConnection->(Write: 'GET / HTTP/1.0\r\n\r\n')]
[Var: 'Result' = $myConnection->(Wait: 60, Net_WaitRead)]
[Fail_If: $Result == Net_WaitTimeOut, (-1), 'TCP Timeout']
[Variable: 'Output' = $myConnection->(Read: 32768)]
[Output: $Output]

<html><head><title>HTML Document</title></head>>body> ...