unique recipient list

 - to prevent dupes being normally filtered by sendmail(8)

diff --git a/perlmail-sendmail b/perlmail-sendmail
index 4831db2..3cf3f3f 100755 (executable)
--- a/perlmail-sendmail
+++ b/perlmail-sendmail
@@ -231,7 +231,11 @@ my $from_headername;
        }
 
 my $exitcode=0;
-my @rcpts=(@addr ? @addr : (undef())); # !defined($rcpt) if we have no recipients
+# !defined($rcpt) if we have no recipients
+# make the list unique to prevent dupes being normally filtered by sendmail(8)
+# one '{' is block-wrapper, another '{' is hash-indirection!
+my @rcpts=keys(%{{ map(($_=>1),(@addr ? @addr : (undef()))) }});
+
 my $stdin_body=(@rcpts<=1 ? undef() : do {     # store input data only if it will be used multiple times
                local $/=undef();
                <STDIN>;