I tried your script, and the page is blank because the postscript anchor is centered by default, and your items are at the extreme top and bottom. Additionally, if you read the perldoc for the postscript method, it states if BOTH pageheight and pagewidth are specified, pagewidth is only used..... that lops off your top and bottom from view. The following works for me, on my smaller screen. 
#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw=MainWindow->new(-title=>"Print out the canvas");
my $c=$mw->Scrolled("Canvas")->pack(-expand=>1,-fill=>'both');
my $canvas=$c->Subwidget("canvas");
$canvas->createLine(100,100,20,20,-arrow=>'both',-arrowshape=>[10,10,1
+0]);
$canvas->createOval(100,80,65,75,-fill=>"blue");
$canvas->createRectangle(30,50,60,80, -fill=>"red",-width=>5);
$canvas->createText(150,1100,-text=>"check postscript",-justify=>"left
+");
$canvas->createOval(150,1150,300,1300,-fill=>"blue");
$canvas->createRectangle(150,1300,400,1350, -fill=>"red",-width=>5);
$canvas->configure(-scrollregion=>[$canvas->bbox("all")]);
$canvas->update();

my $button=$canvas->Button(-text=>"Print",-command=>\&buttonDo)
                            ->pack(-side=>"bottom");
MainLoop;
sub buttonDo{
    $canvas->update;
    my @coord=$canvas->bbox('all');    
    my $maxwidth=$coord[2];    
    my $maxheight=$coord[3];
    $canvas->postscript(    '-x'=>'0','-y'=>'0',
                -colormode=>'color',
                            -file=> "$0.ps",
                           -rotate=>0,
                           -width=>$maxwidth,
                        -height=>$maxheight,
                           -pageanchor => 'n',
                           -pageheight=>'8.0 i',  #to fit my screen
                );
#    system("lpr -S serverN-P printerN file.ps") == 0 or die $!;
    }

[download]
I'm not really a human, but I play one on earth CandyGram for Mongo

In reply to Re: $canvas->postscript method - unexpected result by zentara
in thread $canvas->postscript method - unexpected result by cta

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