BEGIN blocks in Perl -


Searching the Internet, I think the BEGIN block will be evaluated and executed in the compiling phase. But can @inc or other variables be inherited?

Below I've written the test for the directory structure as follows: 

  | - alexpackages | | - alex1.pm | `- alex2.pm | - foo.pl` - main.pl   
 for each file:  
 cat Alex package / alex1.pm  
  package alex1; Sub foo () {print "this is alex1 :: foo \ n"; } 1;   
 cat Alex package / alex2.pm  
  package alex2; Sub foo2 () {print "this is islex2 :: foo2 \ n"; } 1;   
 cat foo.pl  
  alex1 :: foo ();   
 cat main.pl  
  BEGIN {push (@inc, '~ / programmer / perl / alex package '); } Use strict; Use warnings; Use Alex 1; Use Alex 2; # Alex1 :: foo (); # 1. This works fine system ("perl foo.pl"); # 2. This fails   
 The way my program indicates that @inc does not work for a new system call. I think the system call system environment will not be inherited, am I right?  
 And can I create environment variables in the following system calls?   
 
 
 processes  system  by   Variable, but the process of  @INC  is only a global global variable, not a system environment variable that is not visible outside of the Perl program.  
 Some notes on your code  
     
  •  
     Package names should be globally, they should be capitalized, so your package should be  Alex 1  And  Alex 2 , in the file  alexpackages / Alex1.pm  and  alexpackages / Alex2.pm    
  •  
      lib  is best to manipulate pragma by  @INC , so  
      use Lib '~ / programs / perl / The best way to use a prototype is to paral sub-routine, so  subfoo ()  should be just  subfoo    
  •  
     You can like to use to copy the calling code in a package's symbols. By the way, when you call it, you do not need to fully qualify your suburban name, like  foo ()  instead of  Alex1 :: foo ()  < / P>   
     The code will look like  
      main.pl   
      Strictly use; Use warnings; Use Lib '~ / programs / perl / alexpackages'; Alex 1; foo ();   
      ~ / programs / perl / alexpackages / Alex 1.pm   
      package Alex 1; Strict use; Use warnings; Use the base 'exporter'; Our @EXPORT = qw / foo /; Sub foo {print} "this is Alex 1 :: fu \ n"; } 1;

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