newbie question:operation @INC

iwanthome has asked for the wisdom of the Perl Monks concerning the following question:

I use following script add my own lib directory to @INC,

#!/usr/bin/perl
unshift (@INC,"/data/zht/perl");
foreach(@INC) {  print; }
[download]

But after scirpt running ,I use "perl -V" to display @INC,why I can't see my lib directory ?

If my script can running concurrent,will it add duplicate my lib directory to @INC ?

thanks!

Comment on newbie question:operation @INC Download Code

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Re: newbie question:operation @INC by pbeckingham (Parson) on Mar 30, 2004 at 03:20 UTC
Using `perl -V` shows the `@INC` compiled into your perl. You are making a runtime modification to @INC. The latter does not affect the former. Or in other words, your scripts must modify `@INC` on every invocation.	[reply] [d/l] [select]
Re: newbie question:operation @INC by jZed (Prior) on Mar 30, 2004 at 03:21 UTC
Your code only modifies @INC for the duration of your script. To modify @INC in your environment, set the PERL5LIB environment variable in your shell, not in a script.	[reply]
Re: newbie question:operation @INC by Fletch (Bishop) on Mar 30, 2004 at 03:23 UTC
a) changing `@INC` at runtime won't work for modules (subsequent evals or requires will see the change, but not any uses); b) what you've done in no way modifies `@INC` for any subsequent invocations of perl. If you want to permanently modify it you need to set `PERL5LIB` in the environment, use the `-I` command line switch each time, or recompile perl. See `perldoc lib` and `perldoc perlrun` and read carefully.	[reply] [d/l] [select]
Re: newbie question:operation @INC by MarkM (Curate) on Mar 30, 2004 at 03:20 UTC
What do you mean 'after script running, I use "perl -V"'? `@INC` is local to the script. It doesn't affect the parent, nor is a modified `@INC` automatically inherited to a child process. If you need to modify `@INC` for a script that you do not wish to alter, try setting the environment variable PERL5LIB. See "perlrun" for more information.	[reply] [d/l] [select]
Re: newbie question:operation @INC by Mr. Muskrat (Canon) on Mar 30, 2004 at 03:33 UTC
You could always see it like this: `perl '-Mlib qw(/data/zht/perl)' -V` update: Although, that's probably not what you really want...	[reply] [d/l]
Re: newbie question:operation @INC by iwanthome (Beadle) on Mar 30, 2004 at 04:07 UTC
thanks for everyone! I got it!	[reply]