in reply to Calculated position incorrect when using regex in text file that also contains binary info

Works fine for me:

use strict;
use warnings;
use Test::More;

my $pdf = <<'EOT';
/CapHeight 667
>>
endobj 
1 0 obj 
<<
/Subtype /Type1C
/Length 1194
2 0 obj 
>>
stream
3 0 obj 
  BXTBMO+URWTypewriterTOT-LigNar %øøø
                                     ûûúNú% Lm
÷/÷>¦ 7D(URW)++,Copyright 2003 by (URW)++ Design & Development/FSType 
+4 def    - B F H J O S   r ¡S»OÑûb&#49912;ø&#1400;÷Å÷°Àø÷K{zwû
}}û}ø­Ô{ûp{|}¾}ü­}}X{|}øMÅ}µ÷g°÷4µµÄ÷¢Áø£zÜ|k}÷&#899;ªr¨°m\\Hf|oaviZb
+{~&#532;¸¬×©v¡¤tuJY<Z{hYso^P4ÇUî&#7980;&#1708;.÷!±´e~L~u^r^sP
                            a±ÊÕ&#303;÷
.û.û-Þ/÷ÖÀ¢º®¥­}wH{Ue?^±lr©zº±´«¼¥©©¤´º±|p¤¨l^dòûIµ÷#µø+
´oµ±Ã÷ÐÁ¬ø.uovat_wJY¨¾{~~zuj¤vo¬º~Ѹ¯§­¶Ïø
                                          ²|3{zI\\ÎsO°8=1û\'û#Ý-÷¹¯®û-
+÷Ø·®|l©­gfAGfsken^uZÛ÷
           ÊÖï´ø´öÜÞÜKÁè÷.øLz4|~±}ûê}}e|~÷6|k}ðløãuyyuux¡¡¡¢ytñ´ø´oµ
+ðÁ÷ÁØ÷/øLz3|~²}ûê}}d|~÷=|e}÷i¸ïÀÉà&#1653;_9û}}e|~÷=|d}÷îSÁ%>TfIu ´
+ø´oµðÁÐ÷/øLz3|~²}ûê}}d|~÷M|U}÷\\&#1765;º¢0©}rec{rqyy{wød÷K¶
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 ¶

  Ò
   
÷ø\\
endstream 
endobj 
4 0 obj 
<<
/Length 422
>>
EOT

my @tests = (
    { no => 1, start => 26, end => 33 },
    { no => 2, start => 68, end => 75 },
    { no => 3, start => 87, end => 94 },
    { no => 4, start => 1315, end => 1322 },
);

plan tests => 2 * @tests;
for my $t (@tests) {
    my $result = $pdf =~ qr/^$t->{no} 0 obj/m;
    is $-[0], $t->{start}, "No $t->{no} first match starts at $t->{sta
+rt}";
    is $+[0], $t->{end},   "No $t->{no} first match ends at $t->{end}"
+;
}

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Perl 5.20.3 on Linux

  • Comment on Re: Calculated position incorrect when using regex in text file that also contains binary info
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Re^2: Calculated position incorrect when using regex in text file that also contains binary info
by geertvc (Sexton) on Jun 17, 2020 at 05:35 UTC
    Hello hippo,

    I just tried your code on a Windows 10 machine and here it fails. Result: 

    1..8
ok 1 - No 1 first match starts at 26
ok 2 - No 1 first match ends at 33
ok 3 - No 2 first match starts at 68
ok 4 - No 2 first match ends at 75
ok 5 - No 3 first match starts at 87
ok 6 - No 3 first match ends at 94
not ok 7 - No 4 first match starts at 1315
#   Failed test 'No 4 first match starts at 1315'
#   at E:\AppData\Programming\Perl\ReadFile/hippo.pl line 50.
#          got: '1139'
#     expected: '1315'
not ok 8 - No 4 first match ends at 1322
#   Failed test 'No 4 first match ends at 1322'
#   at E:\AppData\Programming\Perl\ReadFile/hippo.pl line 51.
#          got: '1146'
#     expected: '1322'

    [download]
    Even the "got" values (calculated based on the Windows OS) are not correct when checking the location of the items in a text editor (I'm using NPP as text editor) in Windows. It should be 923 and 930 for the 4th object (as opposed to 1139 and 1146 in your script result).

    So, "a" conclusion might be that Windows (once again) differs from Linux in the way files are handled.

    Would there be a need to open the file with a specific encoding?

    Best,
    Geert
[reply]
[d/l]
      So, "a" conclusion might be that Windows (once again) differs from Linux in the way files are handled.

      Quite probably. Having no recent experience of MS Windows I'm not in a position to help you further, unfortunately. In your shoes I would try to persist with the SSCCE, however. The fact that it currently fails shows the problem in isolation which might help to solve it. Good luck.

[reply]

      Hi

      The proper way to share binary data inside perl programs is to use Data::Dump::dd()

      This is especially true if you share that file on the internet

      Without this you have no basis for any conclusions

[reply]

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