I think what's happening is this:

• The master thread starts the slave thread
• The master thread then waits for messages from the slave to appear in a shared message queue
• The slave thread dies before it gets to send even a first message
• As a result, the master thread never joins the slave thread, and this causes the error message to not be printed

Below is a piece of code that illustrates this:

use strict;

use threads;
use threads::shared;

my $fct = 
        sub {
#            eval {require Blah; Blah->import()} or print $@; 
            require Blah; Blah->import(); 
        };
my $thr = threads->new($fct);
#$thr->join();
[download]

When executed as is, it produces the following output:

Perl exited with active threads:
        1 running and unjoined
        0 finished and unjoined
        0 running and detached
[download]

If I remove the comment in front of the last line (the join call), then I get error message:

Thread 1 terminated abnormally: Can't locate Blah.pm in @INC (@INC con
+tains: etc...
[download]

Note also that the eval {} trick doesn't seem to make any difference. In other words, if I remove the comment in from of the eval {} line but leave the join() statement commented out, I still don't get the error message.

Note also that the silent dying does not happen if, for example, the error is caused by a division by zero instead of a non-existant include file.

Also interesting is the fact that if I do "use Blah;" instead of "require Blah; Blah->import()", then I see the error message, even if the join call is commented out.

In case you are wondering why I use a require instead of use, it's because loading the Blah module may end up loading modules which are not thread-safe. Therefore, I want to load the module at run-time, not at compile time (as explained on this node: http://www.perlmonks.org/?node_id=288022).

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