[Mapserver-users] mapscript and XBase cause Out of memory error and/or premature endof script headers error

Fri Jan 3 14:50:56 EST 2003

Thanks, Lowell.  New discoveries...

The CGI module seems to be the problem.

The following bare-bones script works perfectly when the "#use CGI;" is
commented out:

#!/usr/bin/perl -w
use strict;
BEGIN { unshift(@INC, ('/usr/home/gisweb/local/lib',
'/usr/home/gisweb/local/lib/perl5/site_perl/5.005/i386-freebsd'));}
use mapscript;
use XBase;
use CGI;

my $mapfilename = "/usr/home/gisweb/gis/proj/berk/b20.map";
my $image_path = '/usr/home/gisweb/www/docs/gis/scratch/';
my $image_virtual_path = '/gis/scratch/';
my $image_id = $$ . time() . ".png";

my $map = new mapObj($mapfilename) or die('Unable to open mapfile.');
my $img = $map->draw() or die('Unable to draw map');
binmode STDOUT;
$img->saveImage($image_path .
$image_id,$mapscript::MS_PNG,$map->{transparent},$map->{interlace},95);
my $recnumb = 3;
my $table = new XBase '/usr/home/gisweb/gis/data/berk/wa_b.dbf'
        or die XBase->errstr;
my @querydata = $table->get_record($recnumb);
my $block_result = $querydata[1];

print "Content-type: text/html\n\n";
print "<html><body>\n";
print "XBase output:<br>\n";
print "$block_result!\n";
print "<p>Mapscript output:<br>\n";
print "<img src=\"$image_virtual_path";
print "$image_id\" border=\"1\">\n";
print "</body></html>\n"

# --- End of ms_test5.cgi --- #

But...when run with "use CGI;" uncommented, the image is corrupt and the
following message appears in the apache error_log:

gd-png:  fatal libpng error: Out of Memory
gd-png error: setjmp returns error condition

When run in the command line (as "perl ms_test5.cgi"), the program also
runs perfectly.

So, if the solution involves ulink/unlink, the shell builtin, how do I
take advantage of that builtin command if the program is running within
the apache/CGI environment?

Thanks again for your help,

Jonathan

On Fri, 2003-01-03 at 06:10, Lowell Filak wrote:
> The only thing I can seem to locate right now is the shell built-in command ulimit/unlimit .
> Possibly the shell that the cgi is being run in needs unlimit set.?
> All this is assuming that when you receive the out-of-memory error your watching top and can clearly see that there is plenty of memory left.?
> HTH
> Lowell F.
> 
> The following message was sent by "Jonathan W. Lowe" <jlowe at giswebsite.com> on 02 Jan 2003 16:34:07 -0800.
> 
> > List:
> > 
> > Perl mapscript in combination with the perl XBase and CGI modules works
> > very well in my Redhat 8 development environment, but when moving the
> > code to the production FreeBSD environment, the following problem
> > results:
> > 
> > A program containing the statements...
> > 
> > 	use mapscript;
> > 	use XBase;
> > 
> > ...runs the mapscript portions correctly when just the "use XBase;" line
> > is commented out.
> > 
> > The same program runs the XBase portions correctly when just the "use
> > mapscript;" line is commented out.
> > 
> > The line causing problems when both modules are running contains the
> > following  perl mapscript command:
> > 
> > 	my $img = $map->draw() or die('Unable to draw map');
> > 
> > The resulting line in the apache error_log reads:
> > 
> > 	Out of memory!
> > 	[Thu Jan  2 16:09:25 2003] [error] Premature end of script
> > headers...etc
> > 
> > The only posting referring to "Out of memory" in this context refers to
> > SWIG and is a couple of years old.
> > 
> > Any ideas for resolving this problem?
> > 
> > Regards,
> > Jonathan W. Lowe
> > 
> > _______________________________________________
> > Mapserver-users mailing list
> > Mapserver-users at lists.gis.umn.edu
> > http://lists.gis.umn.edu/mailman/listinfo/mapserver-users
> 
> 