Passing arguments

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Re: Passing arguments
by John M. Dlugosz (Monsignor) on Jan 28, 2004 at 21:50 UTC

@RecivedArray= @ARGV;
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Re: Passing arguments
by Roy Johnson (Monsignor) on Jan 28, 2004 at 22:09 UTC

system('perl', 'script2.pl', @theArray);
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@ReceivedArray = @ARGV;
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The PerlMonk tr/// Advocate

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Re: Passing arguments
by Zaxo (Archbishop) on Jan 28, 2004 at 21:56 UTC

This logic is probably wrong:

if ($#ARGV != 0) {
    die " no argument was passed\n";
}
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system

system( '/path/to/perl', '/path/to/script2.pl', @theArray) and die $?, $!;

After Compline,
Zaxo

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Re: Passing arguments
by blue_cowdawg (Monsignor) on Jan 28, 2004 at 21:57 UTC

Can someone tell me what is the problem of the way I am passing the array?

Check out this experiment:

$ cat argvtest.pl
printf "I saw %d arguments\n",$#ARGV+1; #show how many
@argsin=@ARGV; # Snarf in the argnuments
 
printf "They were \"%s\"\n",join(",",@argsin); # and what
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$ perl argvtest.pl 1 2 3 4
I saw 4 arguments

They were "1,2,3,4"
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$#ARGV

@ARGV

With that in mind your test should look something like:

if ( $#ARGV < 0 ) { # NOTE: not != 0 
    printf "I expected an argument not simple refutation\n";
    exit(0);
}
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UPDATE: Re-reading your original post I picked up on something...

You tried:

@RecievedArray=$ARGV[0];
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@ARGV

scalars

@ARGV

I set up another experiment just to demonstrate what is going on:

use Data::Dumper;
 
@ry=qw/ a b c d /;
@ry2=$ry[0];
 
printf "First array:\n";
print Dumper(\@ry);
 
printf "Second array:\n";
print Dumper(\@ry2);
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First array:
$VAR1 = [
          'a',
          'b',
          'c',
          'd'
        ];
Second array:
$VAR1 = [
          'a'
        ];
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Hope all this helps.

Peter L. Berghold -- Unix Professional Peter at Berghold dot Net
	Dog trainer, dog agility exhibitor, brewer of fine Belgian style ales. Happiness is a warm, tired, contented dog curled up at your side and a good Belgian ale in your chalice.

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Re: Passing arguments
by monktim (Friar) on Jan 28, 2004 at 21:53 UTC

#in my calling script
my @array = ('a','b','c');
system(qq(perl C:\\script2.pl @array));
print "system failed.  [$?]: $!" if ($?);

#if args contain spaces
my @array = ('a 1','b 2','c 3');
my $args;
$args .= '"'.$_.'" ' foreach (@array);
system(qq/perl C:\\Backup\\script2.pl $args/);
print "system failed.  [$?]: $!" if ($?);

# Script2.pl
my @RecivedArray = @ARGV;;
print join(',',@RecivedArray);
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Update

system

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Re: Passing arguments
by revdiablo (Prior) on Jan 28, 2004 at 21:59 UTC

To generalize your question, you are looking for a method of Inter-Process Communication. There are many ways to do this, from your method (command line arguments), to a simple text file, to a full blown client-server arrangement. The type of IPC one uses depends on the situation at hand. For lots of documentation on the subject, check out perldoc perlipc.

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Re: Passing arguments
by NetWallah (Canon) on Jan 29, 2004 at 05:50 UTC

As others have suggested, there are several hazards you will encounter when trying to pass parameters using the shell (system call).

Some of these are:

Spaces in data
Binary data
structured data (AoA or HoA etc)
Special chars in data like < ^ >

For a more general solution, you may want to consider using the storable Module, which can be used thus:

    #In Calling program
    use Storable; 
    store(\@array, "filename");

    # later , in Called program ..
    $aref = retrieve("filename");         # Get a ref or
    @array = @{ retrieve("filename") };   # direct into array
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"When you are faced with a dilemma, might as well make dilemmanade. "

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Re: Passing arguments
by ysth (Canon) on Jan 28, 2004 at 21:55 UTC

$#ARGV is the last used index in @ARGV. If @ARGV contains 1 element, $#ARGV will be zero. It's -1 if @ARGV is empty. You should use if (@ARGV) instead.

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