Automatically log out of a menu. 1

[maxcrook]

Hi.

I have written a menu system in Perl.

The problem is that sometimes the users don't log out at the end of the day. I'd like to put a routine in which will exit the menu and logout after 60 minutes of inactivity.

Any ideas?

Thanks in advance.

 

[fishiface]

You need signals and alarms. Every time you read input, you set an alarm first.

sub read_input {
  local $SIG{ALRM} = sub { die "session timed out" };
  alarm 3600;
  my $input = <STDIN>;
  alarm 0;
  return $input;
};

if <STDIN> returns first, the alarm is cancelled. If the alarm fires first, the program dies. If you want to do any clean-up, you could put it in an END block or use the more elaborate

sub read_input {
  my $input;
  eval {
    local $SIG{ALRM} = sub { die 'session timed out' };
    alarm 3600;
    $input = <STDIN>;
    alarm 0;
  }
  if ( $@ && $_ eq 'session timed out' ) {
    # clean-up code here
    exit;
  }
  return $input;
};

Yours,

f

&quot;As soon as we started programming, we found to our surprise that it wasn't as easy to get programs right as we had thought. Debugging had to be discovered. I can remember the exact instant when I realized that a large part of my life from then on was going to be spent in finding mistakes in my own programs.&quot;
--Maurice Wilkes

 

[maxcrook]

Excellent. Just the job.

Thanks.