Ok so now I'm confused. I was able to corrupt the CRC on a zip file. The unzip utility run with the -t shows the corruption 
# unzip -t bad.zip
Archive:  bad.zip
    testing: testfile.txt             OK
    testing: testfile2.txt            bad CRC 32e1dbe6  (should be 32f
+0dbe6)
At least one error was detected in bad.zip.

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But when I run the ziptest.pl utility from the examples directory it shows the CRC as good 
# ./ziptest.pl bad.zip
 Length    Size         Last Modified         CRC-32  Name
-------- --------  ------------------------  -------- ----
      26       14  Mon Aug 28 18:07:58 2017  75b0ca95 testfile.txt
      15        9  Mon Aug 28 18:08:10 2017  32e1dbe6 testfile2.txt
All CRCs check OK

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So what exactly is $member->crc32 doing? Shouldn't it be checking the crc listing as expected in the zip file and not getting the CRC after the file is extracted?

In reply to Re^4: File integrity checker by roperl
in thread File integrity checker by roperl

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