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.
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
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?