I really don't think you understand what the utf8 pragma does. Here's another quote from the documentation (first line of the description):

"The use utf8 pragma tells the Perl parser to allow UTF-8 in the program text in the current lexical scope ..."

It has nothing to do with the:

• flagging variables ("getting $scandir flagged as UTF-8")
• encoding of STDIN, STDOUT or STDERR ("perl -CS ...")
• encoding of @ARGV elements ("perl -CA ...")

Let me reiterate the quote I provided in my earlier post from the utf8 documentation:

"Do not use this pragma for anything else than telling Perl that your script is written in UTF-8."

It has nothing to do with data read into the script, data processed by the script, data generated by the script or data output by the script. It's only about the text used to write the script and how Perl should parse that source text.

It has nothing to do with the: encoding of STDIN ... encoding of @ARGV elements

Correct.

It's only about the text used to write the script and how Perl should parse that source text.

Yes, so...

use utf8;

my $scandir = 'something with umlauts it it';
#              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
# ...is this string literal not part of the source?
[download]

It has nothing to do with flagging variables

#!/usr/bin/perl

use strict;
use Devel::Peek;

{
    use utf8;
    my $var = 'für';
    print Dump \$var;
}

my $var = 'für';
print Dump \$var;

use utf8;

my $scandir = 'something with umlauts it it';
[download]

That's exactly the same code you invented, five nodes back, in your original post in this thread: "Re^2: treat files with umlauts (utf)". It is not code the OP posted (or even described in his narrative). My response is unchanged.

# ...is this string literal not part of the source?
[download]

That string literal is only part of the source you've invented.

...
use Devel::Peek;
...
[download]

Posting code without explaining why you're doing so is not particularly helpful.

If you're referring to the output from that containing:

FLAGS = (PADMY,POK,pPOK,UTF8)
[download]

Then the UTF8 part of that is caused by the umlaut in 'für'. But, the OP's posted code contains no umlauts. Only your invented code contains umlauts.

Change 'für' to 'fur', and you'll get:

FLAGS = (PADMY,POK,pPOK)
[download]

Just like the OP's posted code, this does not contain any umlauts and there's no UTF8 in the output.

You can keep inventing code that requires use utf8 all you want but the OP's posted code contains no umlauts (or any other characters) that require use utf8.

Please be very clear on these points:

• The OP's posted code does not contain umlauts.
• The OP's posted code does not include an assignment to $scandir.
• the OP's posted code does not require use utf8;.

-- Ken