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    <p>Have you tried swapping out the <code>BEGIN{}</code> block for an <code>INIT{}</code> block? That's the standard approach for things like modperl which use the "compile-once, run-many" model, as you need to initialize things anew on each separate run, not just once during the compile.</p> <p>But I have to ask why it's all in special block anyway. Why don't you just make some sort of <code>prepare_db_connection()</code> function, and then call it as you need to when the program starts up?</p> <p>Something that won't work in a <code>BEGIN{}</code> will also have the same problem if it's main-line code in a module file that gets <code>use</code>d. That's another possible reason to use an <code>INIT{}</code> block.</p> <p>I've also seen deadly-embrace problems of mutual recursion that have to be unravelled using something like an <code>require</code> instead of <code>use</code>, or an <code>INIT{}</code> instead of a <code>BEGIN{}</code>. But that's pretty rare.</p> <p>Consider this program:</p> <pre><code>% cat sto-INIT-eg #!/usr/bin/perl -l print " PRINT: main running"; die " DIE: main dying\n"; die "DIE XXX /* NOTREACHED */"; END { print "1st END: done running" } CHECK { print "1st CHECK: done compiling" } INIT { print "1st INIT: started running" } END { print "2nd END: done running" } BEGIN { print "1st BEGIN: still compiling" } INIT { print "2nd INIT: started running" } BEGIN { print "2nd BEGIN: still compiling" } CHECK { print "2nd CHECK: done compiling" } END { print "3rd END: done running" } </code></pre> <p>When compiled only, it produces:</p> <pre><code>% perl -c sto-INIT-eg 1st BEGIN: still compiling 2nd BEGIN: still compiling 2nd CHECK: done compiling 1st CHECK: done compiling sto-INIT-eg syntax OK </code></pre> <p>While when compiled <em>and</em> executed, it produces this:</p> <pre><code>% perl sto-INIT-eg 1st BEGIN: still compiling 2nd BEGIN: still compiling 2nd CHECK: done compiling 1st CHECK: done compiling 1st INIT: started running 2nd INIT: started running PRINT: main running DIE: main dying 3rd END: done running 2nd END: done running 1st END: done running </code></pre> <p>And the shell reports an exit of 255, per the <code>die</code>.</p> <p>You should be able to arrange to have the connection happen when you need it to, even if a <code>BEGIN{}</code> proves too early. </p> <p>Hm, just remembered. There's no chance you're doing something with <code>DATA</code> in a <code>BEGIN{}</code>, is there? That's not set up till the interpreter runs; it's not open to the compiler.</p>
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