Hi everyone! So I'm trying to make sure NFS shares are properly mounted by using a small perl script, along side a much larger program. It uses utime(undef,undef,"/pathtoshare") to make sure the path is still accessible. I've tried to wrap the utime function in an alarmed eval without success. It seems alarm doesn't get signaled. Example: - Mount client to NFS share - run test.pl - OK - stop nfs service on server - run test.pl - flop without alarm (waits about 120 seconds) Here is the relevant portion of the code. 
      print "Evaluating... \n";
      eval{
         local $SIG{ALRM} = sub {
            $sys_check_mount{$mount_server} = 0;
            print "Alarm!";
            exit();
         };
         alarm(5);
         print "Alarm Set... Trying system commands... \n";
         if (-e $mount_server_check_path && utime(undef, undef, "$moun
+t_server_check_path/mount_check")){
            #print "OK\n";
            $sys_check_mount{$mount_server} = 1;
         }else{
            #print "Broken\n";
            $sys_check_mount{$mount_server} = 0;
            push (@mount_server_broken,$mount_server);
         }
         alarm(0);
         print "Reset Alarm... \n";
      }
   }

[download]
Ideally the script shouldn't exit, but rather return something from the eval but I'm not sure how to return from the local $SIG{ALRM}... Any help would be greatly appreciated :)

In reply to Alarm and blocking I/O. by expresspotato

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