in reply to Control Structures

I use something similar to the following in most of my cgi scripts when making system calls. 
use CGI::Carp qw(fatalsToBrowser);

# rest of script

my $CMD="some command";

 system("$CMD");
 ( $? == 0 ) ? print "job success\n" : print "job failure\n";

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Ted
--
"Men have become the tools of their tools."
  --Henry David Thoreau

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Re^2: Control Structures
by ghenry (Vicar) on Apr 29, 2005 at 13:10 UTC

    I love the look of this, because I really wanted to make the code look cleaner and I have been looking for a chance to use the Ternary Conditional Operator.

    Could I swap out the print statements for subroutine calls and move the success and failure things to something like &failure and &success?

    Something like:

    my $CMD="some command";

 system("$CMD");
 ( $? == 0 ) ? &success($time, $hostname) : &failure($time, $hostname)
+;

    [download]

    and then shift these scalars inside the subroutines?

    Thanks.

    Walking the road to enlightenment... I found a penguin and a camel on the way.....
    Fancy a yourname@perl.me.uk? Just ask!!!
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      I'll answer my own question ;-)

      I tried it and it worked!

      For your info:

      Read more... (7 kB)

      Walking the road to enlightenment... I found a penguin and a camel on the way.....
      Fancy a yourname@perl.me.uk? Just ask!!!
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        if (-s "$imagefile" < 700_000_000 and -e "$imagefile") {
        print '<script language="JavaScript">
                var x=window.confirm("Is there a CD/DVD in the drive?"
+)
                if (!x)        
                window.location="http://hostname/cgi-bin/swish.cgi"
                </script>';
              print "\n\nISO not too big and exists. \nBurning the CDR
+W.\n\n"   
+     
             ."\nPlease be patient, this will take a while...\n\n";
              system "sudo cdrecord -v -eject dev=$device $imagefile";
+          
+       
}

( $? == 0 ) ? &success($date, $time, $hostname, $logdir, $to, $from) :
&failure($date, $time, $hostname, $logdir, $to, $from);

        [download]

        Hmm. That looks like mixed success to me. What happens if the test at the top of the if statement fails? Then $? will be 0 (unless it was fortuitously still set from a previous failed child process), even though cdrecord was never attempted.

        Read more... (950 Bytes)

        the lowliest monk

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