This function is used to test a zip or gzip file for errors.
After the test has been run any bad files are marked as follows....
 | Added file which has been moved |
 | Crc error, corrupt data. |
You should hardly ever need to use this function, any archive format that includes check totals
will be automatically tested. This automatic testing occurs either when the archive file is opened or
when an individual file is extracted or viewed. The only practical use of this function is to force
a test of an entire zip archive rather than wait for them to be tested as you extract or view them.
Any computer file can be damaged by transmission errors. To detect these errors
archive designers have included special check numbers in the file formats.
Note: tar archives do not contain any check numbers, but they are normally transmitted and
stored in a tar.gzip format in which case the gzip part provides the error checking.
Archives can be tested as follows...
- zip archives. When a file is viewed or extracted it is automatically tested.
- tar archives cannot be tested.
- gzip archives are automatically tested when they are opened.
- bzip archives are automatically tested when they are opened.
- zip.gzip archives have their gzip check numbers tested when they are opened, the zip check numbers
are automatically tested when a file is extracted or viewed.
- zip.bzip archives have their bzip2 check numbers tested when they are opened, the zip check numbers
are automatically tested when a file is extracted or viewed.
- tar.gzip archives have their gzip check numbers tested when they are opened.
- tar.bzip2 archives have their bzip2 check numbers tested when they are opened.
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