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POIs it ever safe to combine select(2) and buffered IO for file handles?
 

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  1. POIs it ever safe to combine select(2) and buffered IO for file handles?
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    <p>I am using IO::Select to keep track of a variable number of file handles for reading. Documentation I've come across strongly suggests not to combine the select statement with &lt;> (readline) for reading from the file handles. </p> <p>My situation:</p> <p>I will only ever use each file handle once, i.e. when the select offers me the file handle, it will be completely used and then removed from the select. I will be receiving a hash and a variable number of files. I do not mind if this blocks for a time.</p> <p>For more context, I am a client sending information to be processed by my servers. Each file handle is a different server I'm talking to. Once the server is finished, a hash result will be sent back to me from each one. Inside that hash is a number indicating the number of files to follow.</p> <p>I wish to use readline in order to integrate with existing project code for transferring Perl objects and files.</p> <p>Sample code:</p> <pre><code>my $read_set = IO::Select()-&gt;new; my $count = @agents_to_run; #array comes as an argument for $agent ( @agents_to_run ) { ( $sock, my $peerhost, my $peerport ) = server($config_settings{ $agent }-&gt; { 'Host' },$config_settings{ $agent }-&gt;{ 'Port' }; $read_set-&gt;add( $sock ); } while ( $count &gt; 0) { my @rh_set = IO::Select-&gt;can_read(); for my $rh ( @{ $rh_set } ) { my %results = &lt;$rh&gt;; my $num_files = $results{'numFiles'}; my @files = (); for (my i; i &lt; $num_files; i++) { $files[i]=&lt;$rh&gt;; } #process results, close fh, decrement count, etc } } </code></pre>
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    1. CODo you have some sample code to show what you've done?
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    2. COAdded an example of what I'm trying to do.
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    3. CO`{ my $oldfh = select $rh; $| = 1; select $oldfh; }` is useless for read handles. That's a good thing, because if Perl emptied the buffer after every read as you seem to want, you'd lose data!
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