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Top Forums Shell Programming and Scripting Meaning of 2>/dev/null/ <<EOF ? Post 302517790 by mirni on Wednesday 27th of April 2011 07:47:06 PM
Old 04-27-2011
Code:
/dev/null

is a sink; think of it as a "black hole", where you can dump what you don't want.
By doing 2> /dev/null, you are dumping the stderr.
Code:
$ ls -l nonexistentFile
ls: nonexistentFile: No such file or directory

Code:
$ ls -l nonexistentFile 2>/dev/null

The error message is sent to the sink.

The here-document (<<EOF construct) is used to create a name-less file.
Code:
cmd <<EOF
line1
line2
EOF

is the same as
Code:
cmd file

where file contains:
Code:
line1
line2

This User Gave Thanks to mirni For This Post:
 

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COM_EVENT_SINK(3)							 1							 COM_EVENT_SINK(3)

com_event_sink - Connect events from a COM object to a PHP object

SYNOPSIS
bool com_event_sink (variant $comobject, object $sinkobject, [mixed $sinkinterface]) DESCRIPTION
Instructs COM to sink events generated by $comobject into the PHP object $sinkobject. Be careful how you use this feature; if you are doing something similar to the example below, then it doesn't really make sense to run it in a web server context. PARAMETERS
o $comobject - o $sinkobject -$sinkobject should be an instance of a class with methods named after those of the desired dispinterface; you may use com_print_typeinfo(3) to help generate a template class for this purpose. o $sinkinterface - PHP will attempt to use the default dispinterface type specified by the typelibrary associated with $comobject, but you may override this choice by setting $sinkinterface to the name of the dispinterface that you want to use. RETURN VALUES
Returns TRUE on success or FALSE on failure. EXAMPLES
Example #1 COM event sink example <?php class IEEventSinker { var $terminated = false; function ProgressChange($progress, $progressmax) { echo "Download progress: $progress / $progressmax "; } function DocumentComplete(&$dom, $url) { echo "Document $url complete "; } function OnQuit() { echo "Quit! "; $this->terminated = true; } } $ie = new COM("InternetExplorer.Application"); // note that you don't need the & for PHP 5! $sink = new IEEventSinker(); com_event_sink($ie, $sink, "DWebBrowserEvents2"); $ie->Visible = true; $ie->Navigate("http://www.example.org"); while(!$sink->terminated) { com_message_pump(4000); } $ie = null; ?> SEE ALSO
com_print_typeinfo(3), com_message_pump(3). PHP Documentation Group COM_EVENT_SINK(3)
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