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+**************************************************************************
+* The following are notes for all the Perl tracing scripts,
+*
+* $Id: ALLperl_notes.txt 44 2007-09-17 07:47:20Z brendan $
+*
+* COPYRIGHT: Copyright (c) 2007 Brendan Gregg.
+**************************************************************************
+
+
+* Where did those "BEGIN" subroutine calls come from?
+
+The following counts subroutines from the example program, Code/Perl/hello.pl,
+
+   # pl_subcalls.d
+   Tracing... Hit Ctrl-C to end.
+   ^C
+    FILE                             SUB                                 CALLS
+
+no subroutines were called, so there is no data to output.
+
+Now a similar program is traced, Code/Perl/hello_strict.pl, which uses
+the "strict" pragma,
+
+   # pl_subcalls.d
+   Tracing... Hit Ctrl-C to end.
+   ^C
+    FILE                             SUB                                 CALLS
+    hello_strict.pl                  BEGIN                                   1
+    strict.pm                        bits                                    1
+    strict.pm                        import                                  1
+
+not only were functions from "strict.pm" traced, but a "BEGIN" function
+ran from the "hello_strict.pl" program - which doesn't appear to use "BEGIN",
+
+   # cat -n ../Code/Perl/hello_strict.pl
+        1  #!./perl -w
+        2  
+        3  use strict;
+        4  
+        5  print "Hello World!\n";
+
+Perl appears to add a BEGIN block to process the "use" keyword. This makes
+some degree of sense.
+