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?