I was going to en.wikipedia.org to get the contents of a zip file and decoded the top of the files as:
and I get a problem: nowhere is the desction of the fields:
File last modification time
File last modification date
And so I let (for the moment) the number found there.
A seach using “File last modification” in the wikipedia file returns only these two descriptions.
The question is: how can I decode the returned values to get the real date and time ?
Ideas ?
In the mean time, I will create some texts files with only some words in them, create a zip from these files and try reverse engineering (in case I am able to understand what I get, reading the zip as above AND with a Hex Dump application.
TIA
BTW: the “Comicinfo.xml” file was (usually) added after the orogonal zip creator… creates it. But I do not know why this person do that (besde the obvious advertising (reading the file, this become obvious, more obvious when you have the chance to get the original zip file…).
Zip timestamps are stored in the ancient MS-DOS format. Here’s a method that takes the two UInt16’s of the timestamp and converts them into a Xojo DateTime object.
Function ConvertDate(Dt As UInt16, tm As UInt16) As DateTime
' Convert the passed MS-DOS style date and time into a DateTime object.
' The DOS format has a resolution of two seconds, no concept of time zones,
' and is valid for dates between 1/1/1980 and 12/31/2107
Dim h, m, s, dom, mon, year As Integer
h = ShiftRight(tm, 11)
m = ShiftRight(tm, 5) And &h3F
s = (tm And &h1F) * 2
dom = dt And &h1F
mon = ShiftRight(dt, 5) And &h0F
year = (ShiftRight(dt, 9) And &h7F) + 1980
Return New DateTime(year, mon, dom, h, m, s)
End Function
If you need more details about zip files - PKWARE, the inventor and maintainer of the file format, maintains a specification document named APPNOTE.TXT. Enter those two names into your preferred search engine to find it.
Andrew, Stefan: THANK YOU. I will follow your advices by tomorrox (I slept the whole afternoon and need some more rest.
