bash - ssh login verification in perl -

i running following lines of code in perl script find df output of remote machines. works fine , gather info in @df_ret untill until ssh key uptodate. if public corrupted or changed, not showing sign of error in script. if run manually asked password.

@df_ret = split /\n/, `ssh -q $server 'df -hp'`; 

is there way can verify if ssh login successful perl script line should executed else not. been finding many searches on not reach one. help?

i have got 1 solution working below; #!/usr/local/bin/perl

my $line  = `ssh $server -o 'batchmode=yes' -o 'connectionattempts=1' true`; $error = `echo $?`;  print "error = $error";  if($error == 0 ) {     print "this good";     @df_ret = split /\n/, `ssh -q $server 'df -hp'`; } else {     print "this bad"; }