Re^2: When can the character length of a Perl Scalar become an issue?

I'm not sure what this tells me? It all ran fine. As I said sometimes it trucates sometimes not.

Enter h or 'h h' for help, or 'man perldebug' for more help.

main::(./y.pl:6):       my $derp = 'x' x 30000;
  DB<1> n
main::(./y.pl:7):       my $dom = Mojo::DOM->new('<?xml version="1.0"?
+><herp><derp>Test</derp>
main::(./y.pl:8):       +</herp>');
  DB<1>
main::(./y.pl:9):       say length ( $dom->at( 'derp' )->text );
  DB<1>
4
main::(./y.pl:10):      $dom->at( 'derp' )->content( $derp );
  DB<1>
main::(./y.pl:11):      say length ( $dom->at( 'derp' )->text );
  DB<1>
30000
main::(./y.pl:12):      say $dom;
  DB<1>
<?xml version="1.0"?><herp><derp>xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx (30,000 printed total)</derp>
+</herp>
Debugged program terminated.  Use q to quit or R to restart,
  use o inhibit_exit to avoid stopping after program termination,
  h q, h R or h o to get additional info.
  DB<1>
[download]

Comment on Re^2: When can the character length of a Perl Scalar become an issue? Download Code

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Re^3: When can the character length of a Perl Scalar become an issue? by marto (Cardinal) on Sep 20, 2023 at 15:58 UTC
Purely an SSCCE to illustrate adding 30K characters to an XML node. You're likely doing something in the code you're not showing us that causes the problem.	[reply]
Re^4: When can the character length of a Perl Scalar become an issue? by misterperl (Friar) on Sep 20, 2023 at 16:27 UTC
OK so first I build the scalar- the code just appends values to a long string. It can reach 40,000 or more characters, saved in scalar $E. $E has NO EOL characters. The $E gen code is hard to sanitize. Then $E is appended to a very short file: `open A, ">>$a"; print A "$E\n"; close A;` [download]	[reply] [d/l]
Re^5: When can the character length of a Perl Scalar become an issue? by NERDVANA (Priest) on Sep 22, 2023 at 03:12 UTC
Since files are involved, and appending to files, is there a chance that more than one copy of your script runs at the same time, appending to the same file?	[reply]
Re^5: When can the character length of a Perl Scalar become an issue? by marto (Cardinal) on Sep 21, 2023 at 08:42 UTC
It's better to mark a post as updated. Again without seeing a repeatable example (see previous links) that demonstrates the problem it's difficult to help. `#!/usr/bin/perl use strict; use warnings; my $derp = 'X' x 40000; open (my $fh, '>', 'derp.txt') or die "can't open derp.txt: $!"; print $fh $derp; close($fh);` [download] `ls -al derp.txt -rw------- 1 marto marto 40000 Sep 21 09:37 derp.txt` [download] See also open, three arg open, migrating to modern perl.	[reply] [d/l] [select]
Re^5: When can the character length of a Perl Scalar become an issue? by Anonymous Monk on Sep 21, 2023 at 06:10 UTC
Tough to tell without seeing the gen code... Best guess is some sort of ctrl char (or seq of chars that get resolved to one). If you make it gen the same line twice, does it break in the same place ? Cheers Chris	[reply]