File archiving, compressing etc. are fascinating fields, and as
Wikipedia indicates, the checksum for the header block should
normally be at offset 148, size 8 . It is " 6247" in my
'HlpDict.tar' file before transfer to my iPad using iTunes.
In 'tart':
The checksum is " 6247" (4 leading blanks), and chksum{d
correctly reads it.
But getchk d returns "006247 " (2 trailing blanks)
The problem shows up in line 11 of 'tart'
Sent from my iPad
On 2012-06-04, at 09:36, Eric Iverson <[email protected]> wrote:
> That blows my theory of a problem in J tar create. Probably a difference
> between my interpretation of the tar file spec and 7-zip. Although not the
> same, not that J tar exctract works on the addons tar of the dictionary.
>
> Perhaps you already ave, but it would be helpful if you could document
> exactly what bytes the 7-zip has for its checksum and what bytes J tar x
> things it should have.
>
> On Mon, Jun 4, 2012 at 9:28 AM, Robert Cyr <[email protected]> wrote:
>
>> The file was created with 7-Zip on a 64-bit vista pc.
>>
>> Sent from my iPad
>>
>> On 2012-06-04, at 08:56, Eric Iverson <[email protected]> wrote:
>>
>>> I haven't had a chance to look at this, but if there is a big I expect it
>>> is in tar create. Most of the testing was done with tar 'x' (that is,
>>> extract). Quite a few addons, with quite a range of files and folder
>>> structures extract successfully.
>>>
>>> Can you confirm that the problem you found was with a file that the J tar
>>> created, rather than a file created by standard unix tar.
>>>
>>> If the bug is in J tar create checksum then it is probably easy to figure
>>> out the fix.
>>>
>>> On Sun, Jun 3, 2012 at 3:00 PM, Robert Cyr <[email protected]> wrote:
>>>
>>>> tar defines a var named checksum and uses a function named getchk.
>>>>
>>>> The 4 (out of 8) leading chars of checksum{d are '0', whereas the 4
>>>> leading chars of getchk d are ' '. The other 4 are ok.
>>>>
>>>> This leads to an assertion failure.
>>>>
>>>> Sent from my iPad
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>>>>
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>>
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