use Net::SFTP; 
my $sftp=Net::SFTP->new('abcdef.ud.com',user=>'abcde',password=>'12345678',debug=>1); 
  print "Logged in..."; 
 sftp->cwd('SUBFOLDER'); 
   print "changed directory..."; 
sftp->put('file.txt'); 
     print "putting file"; 
sftp->quit;