perl BEGIN 和END块

[root@node01 perl]# cat a2.pl 
END {print cccccccccccc."
"};  
print "aaaaaaaaaaaaa
";  
BEGIN {print bbbbbbbbbbbbbb."
"}; 
[root@node01 perl]# perl a2.pl 
bbbbbbbbbbbbbb
aaaaaaaaaaaaa
cccccccccccc

BEGIN 代码块最先执行,END代码块最后执行

[root@node01 perl]# cat a2.pl 
require xx;
print "aaaaaaaaaaaaa
";  
BEGIN {print bbbbbbbbbbbbbb."
"}; 
[root@node01 perl]# perl a2.pl 
bbbbbbbbbbbbbb
Can't locate xx.pm in @INC (you may need to install the xx module) (@INC contains: /usr/local/perl/lib/site_perl/5.22.1/x86_64-linux /usr/local/perl/lib/site_perl/5.22.1 
/usr/local/perl/lib/5.22.1/x86_64-linux /usr/local/perl/lib/5.22.1 .) at a2.pl line 1.