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Specify the syntax on markdown blocks to avoid broken output that has class=err
author Dirk Olmes <dirk@xanthippe.ping.de>
date Thu, 19 Dec 2019 10:04:33 +0100
parents 4cd9b65e10e4
children
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97:e99db3bc53c1 98:1d9382b0329b
2 Date: 2007-05-22 2 Date: 2007-05-22
3 Lang: en 3 Lang: en
4 4
5 I had to debug Mule's build for the upcoming 1.4.1 release a bit, especially the packaging of the JCA distribution. I usually use Zipper to open archives, that's why I wrote it in the first place. It turns out that some file extensions are ambiguous, e.g. a file ending in .rar could either be a rar archive or a Java Resource ARchive which is effectively a zip file. Since the rar packager cannot handle zip files I picked up an idea I had in mind for a long time now: file types should not be determined by their extensions but the way the unix file command does it: by looking for certain patterns inside of a file. I implemented the most simple cases in Zipper now: Zip files begin with 5 I had to debug Mule's build for the upcoming 1.4.1 release a bit, especially the packaging of the JCA distribution. I usually use Zipper to open archives, that's why I wrote it in the first place. It turns out that some file extensions are ambiguous, e.g. a file ending in .rar could either be a rar archive or a Java Resource ARchive which is effectively a zip file. Since the rar packager cannot handle zip files I picked up an idea I had in mind for a long time now: file types should not be determined by their extensions but the way the unix file command does it: by looking for certain patterns inside of a file. I implemented the most simple cases in Zipper now: Zip files begin with
6 6
7 :::shell
7 { 'P', 'K', 0x003, 0x004 } 8 { 'P', 'K', 0x003, 0x004 }
8 9
9 and rar files begin with 10 and rar files begin with
10 11
12 :::shell
11 { 'R', 'a', 'r', '!'} 13 { 'R', 'a', 'r', '!'}
12 14
13 straight from the beginning of the file. When opening a file Zipper asks all registered Archive subclasses for their magic bytes and compares them to the first four bytes of the file. I think I will extend this mechanism a bit in the future so in the end all supported archives will be determined by a file's content and not by its file extension any more. 15 straight from the beginning of the file. When opening a file Zipper asks all registered Archive subclasses for their magic bytes and compares them to the first four bytes of the file. I think I will extend this mechanism a bit in the future so in the end all supported archives will be determined by a file's content and not by its file extension any more.