I don't see why hippo's second second suggestion above (the OTOH one) would not cover all your cases:

c:\@Work\Perl\monks>perl -wMstrict -le
"for my $path (
   'scp', 'sss40s1u01:/home/example/test.txt', '/home/example/testdir'
+,
   @ARGV,
   ) {
   print qq{'$path' matches} if $path =~ /^\//;
   }
"  "/any"  "/other/examples"
'/home/example/testdir' matches
'/any' matches
'/other/examples' matches
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(BTW: My own preference for the regex expression would be  m{ \A / }xms rather than  /^\//)