I tried the following:

#!/usr/bin/perl

use strict;
use warnings;

open(my $CMD, "dira |") || die "another text";
# ...
close($CMD);
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But the program still produces the same error message:

Der Befehl "dira" ist entweder falsch geschrieben oder
konnte nicht gefunden werden.
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Not for me:

#!/usr/bin/perl

use strict;
use warnings;

open(my $CMD, "dira |") || die "something else\n";
while( <$CMD> ) {
    print "$_";
}

close($CMD);
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Output:

Can't exec "dira": No such file or directory at ./test.pl line 6.
something else
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This form of open starts a child process. The return result is the child process ID. Thus, your open(...) || die ... will show the error if the child can't be created. You need to check $? to check for errors from the child. See this for an example of checking for errors in this situation.

Thanks. You are right. Examining $? helps to know if the child process executed correctly or not.

Here my sample code:

eval
{
    open my $pipe, "perl --version |";
    my @res = <$pipe>;
    close $pipe;
};

print "Exit Status: " . ($?>>8);
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If I use the not existing command "perl2 --version" then I get the following error message and the exit status 1.

Der Befehl "perl2" ist entweder falsch geschrieben oder
konnte nicht gefunden werden.
Exit Status: 1
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If I use an existing command like "perl --version" then I get the exit status 0 and no error message:

Exit Status: 0
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Problem of course is that I then know the error not directly after the open, but only when the child process exited, that means after the close.