11 ms·

But why doesn't it feel right? Is it the lack of tooling with the Unix nature? (libarchive's tar will sort of do, although the zip files it creates are a bit w

But why doesn't it feel right? Is it the lack of tooling with the Unix nature? (libarchive's tar will sort of do, although the zip files it creates are a bit wacky.)

thayne 8y ago
> But why doesn't it feel right Because it wasn't designed for for unix-like systems. Perhaps most notably, zip files don't have any support for unix-style permissions. Which makes it a bit of a non-starter for containers at least.
- naniwaduni 8y ago
  They do---as an optional extra field. This seems reasonable; it's not even desirable for many archives to include e.g. owner/group information. The zip format has its own odd required metadata (a timestamp in local time!), but for the most part the design of relegating platform-specific metadata to the extra fields seems quite sensible. -UNIX Extra Field (0x000d): The following is the layout of the Unix "extra" block. Note: all fields are stored in Intel low-byte/high-byte order. Value Size Description ----- ---- ----------- (UNIX) 0x000d 2 bytes Tag for this "extra" block type TSize 2 bytes Size for the following data block Atime 4 bytes File last access time Mtime 4 bytes File last modification time Uid 2 bytes File user ID Gid 2 bytes File group ID (var) variable Variable length data field The variable length data field will contain file type specific data. Currently the only values allowed are the original "linked to" file names for hard or symbolic links, and the major and minor device node numbers for character and block device nodes. Since device nodes cannot be either symbolic or hard links, only one set of variable length data is stored. Link files will have the name of the original file stored. This name is NOT NULL terminated. Its size can be determined by checking TSize - 12. Device entries will have eight bytes stored as two 4 byte entries (in little endian format). The first entry will be the major device number, and the second the minor device number. http://www.pkware.com/documents/APPNOTE/APPNOTE_6.2.0.txt http://www.pkware.com/documents/APPNOTE/APPNOTE_6.2.0.txt

But why doesn't it feel right? Is it the lack of tooling with the Unix nature? (libarchive's tar will sort of do, although the zip files it creates are a bit wacky.)

thayne 8y ago

> But why doesn't it feel right Because it wasn't designed for for unix-like systems. Perhaps most notably, zip files don't have any support for unix-style permissions. Which makes it a bit of a non-starter for containers at least.

naniwaduni 8y ago
They do---as an optional extra field. This seems reasonable; it's not even desirable for many archives to include e.g. owner/group information. The zip format has its own odd required metadata (a timestamp in local time!), but for the most part the design of relegating platform-specific metadata to the extra fields seems quite sensible. -UNIX Extra Field (0x000d): The following is the layout of the Unix "extra" block. Note: all fields are stored in Intel low-byte/high-byte order. Value Size Description ----- ---- ----------- (UNIX) 0x000d 2 bytes Tag for this "extra" block type TSize 2 bytes Size for the following data block Atime 4 bytes File last access time Mtime 4 bytes File last modification time Uid 2 bytes File user ID Gid 2 bytes File group ID (var) variable Variable length data field The variable length data field will contain file type specific data. Currently the only values allowed are the original "linked to" file names for hard or symbolic links, and the major and minor device node numbers for character and block device nodes. Since device nodes cannot be either symbolic or hard links, only one set of variable length data is stored. Link files will have the name of the original file stored. This name is NOT NULL terminated. Its size can be determined by checking TSize - 12. Device entries will have eight bytes stored as two 4 byte entries (in little endian format). The first entry will be the major device number, and the second the minor device number. http://www.pkware.com/documents/APPNOTE/APPNOTE_6.2.0.txt http://www.pkware.com/documents/APPNOTE/APPNOTE_6.2.0.txt