Beefy Boxes and Bandwidth Generously Provided by pair Networks
"be consistent"
 
PerlMonks  

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
I need to write an application that forks multiple childs, maintaining for each child a communication channel, so that the childs can send data back to the parent (output and informations about their state).
Reading about interprocess communication, it seemed to me that pipes could solve my problem. Here what I naively wrote :)
#!/usr/bin/perl use strict; use FileHandle; use Data::Dumper; my $childs = { A => { pid => undef, handler => undef, blabla => () }, B => { pid => undef, handler => undef, blabla => () }, C => { pid => undef, handler => undef, blabla => () } }; foreach my $name ( keys %{$childs} ) { $childs->{ $name }->{ handler } = new FileHandle; $childs->{ $name }->{ pid } = $childs->{ $name }->{ handler }->ope +n( "-|" ); if ($childs->{ $name }->{ pid }) { # The child's talking... while(my $line = $childs->{ $name }->{ handler }->getline()) { push @{$childs->{ $name }->{ blabla }}, $line; } } else { # Childs' STDOUTs are read by the parent print "Hi! I'm $name and I'm good!"; exit; } } print Dumper( $childs );
As you can see, I maintain a hash for each child, containing a file handler that is used by the parent to read child's output. But this does not work, because the while-block that read child's output is blocking. This way doesn't seem to be worth further exploring. How could I realize what I've described at the beginning of this node?

In reply to Coping with a large family (interprocess communication) by larsen

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others rifling through the Monastery: (5)
As of 2021-09-28 08:23 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found

    Notices?