Here I suppose the LDAP module that returns last name, gives you "decoded utf8 string". What do you see in log.txt file? and any warning message? 

my $lastname=''; #here put the return value of LDAP
open( my $fh, ">:encoding(UTF-8)", "log.txt") or die $!;
print $fh utf8::is_utf8($lastname) ? 'utf8 flagged,' : 'not utf8 flagg
+ed,';
print $fh $lastname;
close $fh;

[download]

Some string (in this case LDAP)
 |
LDAP module?
 |        <--- here LDAP returns what? is important information
perl
 |
utf8 text
Do you see the manual of LDAP module has 'encoding' or 'binmode' section for this information?

In reply to Re^5: how to output file in Unicode by remiah
in thread how to output file in Unicode by anakin30

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