On Wed, Aug 1, 2012 at 9:08 AM, Paul.G <medur...@yahoo.com.au> wrote:
> The example below is just a test, I need to be able to insert multiple
> values into a command, those values can be either 1, 2 or upto 5.
>
> Below is closer to the working example, but I will read that document and
> to help make a final decision.
>
> # Check Free PV's
> operation_CHECKFREEPVS();
>
> $NEWMIRROR = $MIRROR + $numPV;
>
> if ($numPV ne 0 && $MIRROR le 5) {
> # lvextend
> print "$numPV $NEWMIRROR $MIRROR\n";
> switch ($numPV) {
> case 1 { run("/usr/sbin/lvextend -m $NEWMIRROR -s $sourcelv
> $FreePV[0]"); }
> case 2 { run("/usr/sbin/lvextend -m $NEWMIRROR -s $sourcelv
> $FreePV[0] $FreePV[1]"); }
> case 3 { run("/usr/sbin/lvextend -m $NEWMIRROR -s $sourcelv
> $FreePV[0] $FreePV[1] $FreePV[2]"); }
> case 4 { run("/usr/sbin/lvextend -m $NEWMIRROR -s $sourcelv
> $FreePV[0] $FreePV[1] $FreePV[2] $FreePV[3]"); }
> case 5 { run("/usr/sbin/lvextend -m $NEWMIRROR -s $sourcelv
> $FreePV[0] $FreePV[1] $FreePV[2] $FreePV[3] $FreePV[4]");
> }
> }
> # lvsync
> run("/usr/sbin/lvsync -T $sourcelv");
> logprint "Successful $NEWMIRROR mirrors \t\t synced";
> }
> else {
> cleanexit (10, "FAIL \t\t No Free PV's Available");
> }
>
> return 0;
> }
>
>
>
> ________________________________
> From: John W. Krahn <jwkr...@shaw.ca>
> To: Perl Beginners <beginners@perl.org>
> Sent: Wednesday, 1 August 2012 4:58 PM
> Subject: Re: case statement in perl
>
> Paul.G wrote:
> > Below is an extract from the perl script, the switch/case statement
> seemed like a simple solution.
> >
> >
> >
> > ##################### Mail Program #####################################
> >
> > operation_CHECKFREEPVS();
> > print "$numPV \n";
> > # print "$FreePV[1] $FreePV[0] $numPV\n";
> > if ($numPV ne 0 ) {
> > switch ($numPV) {
> > case 1 { print "$FreePV[0] \n"; }
> > case 2 { print "$FreePV[0] $FreePV[1] \n"; }
> > case 3 { print "$FreePV[0] $FreePV[1] $FreePV[2] \n"; }
> > }
> > }
>
> Couldn't you just do that like this:
>
> if ( @FreePV && @FreePV <= 3 ) {
> print join( ' ', @FreePV ), "\n";
> }
>
>
> > else {
> > print "No PV's available \n";
> > }
>
>
>
> John
> --
> Any intelligent fool can make things bigger and
> more complex... It takes a touch of genius -
> and a lot of courage to move in the opposite
> direction. -- Albert Einstein
>
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> http://learn.perl.org/
>
Why make life so hard as John suggested you check for the number of
arguments and as long as it is less then 5 you simply join them with a
space and you are done with a single line...
No matter what you do you will always have to check the variables that you
are going to push out, right now I could very well feed a parameter that
ends in a ; and then do something like *rm -rf /* which could make a
serious mess of your system...
Personally I would suggest checking the command flags if they are valid,
and do not contain any funny characters before even considdering putting
this in a system call or equivalent.
Regards,
Rob
