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in reply to Re: DBI, fork, and clone.
in thread DBI, fork, and clone.

I have been using the above code successfully since 2007 when it was first posted, but recently I upgraded my Perl to 5.8.8, DBI 1.604, and DBD::Pg 2.10.7.

I'm having the same issue as before where the main process will go haywire and report random query errors. Did something change recently or is there a new workaround?

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Re^3: DBI, fork, and clone.
by Anonymous Monk on Jan 08, 2009 at 08:18 UTC
    Here is the code I was using that is now broken. I have defined $dbh as a global variable using 'our' pragma. 
     if (my $pid = fork) {
      l("D","$restr [$tbn] [se_id:$se->{scenario_exec_id}] forking ($p
+id) $se->{suite_name}:$se->{scenario_name}");
      $V{scenario_exec_childs}->{$se->{scenario_exec_id}}{pid} = $pid;
      $V{scenario_exec_childs}->{$se->{scenario_exec_id}}{start_time} 
+= $before_exec;
      # prepopulate before next cycle for state consistency, $se is re
+ferenced in the $ses array ref in main loop
      $se->{status} = "RUNNING";
      set_scenario_exec_state($se,{ -testbed_id=>$tb_id, -pid=>$pid, -
+start=>"now()", status=>"RUNNING" });
      sleep 2;
    } elsif (defined $pid) {
      $0 = "$restr $tbn SE:$se->{scenario_exec_id}";
      l("D", "top of se fork: " . $dbh);

      # once and for all, I think I have figured out the forking + DBI
+ connection handling issue! 2007-04-23, 
      # we clone the handle, undef it, then copy over the old variable
+ in the new process

      # suppress warning from clone call... I think something is broke
+n with DBI 
      # produces: Can't set DBI::db=HASH(0x82cf704)->{User}: unrecogni
+sed attribute or invalid value at 
      # /volume/perl/lib/site_perl/5.8.5/i386-freebsd/DBI.pm line 648.
      my $saved_warn_handler = $SIG{__WARN__}; $SIG{__WARN__} = sub {}
+;
      my $child_dbh = $dbh->clone(); $SIG{__WARN__} = $saved_warn_hand
+ler;
      l("D", "cloned child_dbh: " . $child_dbh);
      $dbh->{InactiveDestroy} = 1; undef $dbh; $dbh = $child_dbh;

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    20090108 Janitored by Corion: Changed PRE tags to CODE tags, as per Writeup Formatting Tips

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