ustar constant
USTAR (Unix Standard TAR) header format defined in POSIX.1-1988.
The structure of the USTAR Header consists of the following:
Start | End | Field
0 | 100 | Path name, stored as null-terminated string. 100 | 108 | File mode, stored as an octal number in ASCII. 108 | 116 | User id of owner, as octal number in ASCII. 116 | 124 | Group id of owner, as octal number in ASCII. 124 | 136 | Size of file, as octal number in ASCII. 136 | 148 | Modification time of file, number of seconds from epoch, stored as an octal number in ASCII. 148 | 156 | Header checksum, stored as an octal number in ASCII. 156 | 157 | Type flag, determines the kind of header. Note that the meaning of the size field depends on the type. 157 | 257 | Link name, stored as a string. 257 | 263 | Contains the magic value "ustar\x00" to indicate that this is the USTAR format. Full compliance requires user name and group name fields to be set. 263 | 265 | Version. "00" for POSIX standard archives. 265 | 297 | User name, as null-terminated ASCII string. 297 | 329 | Group name, as null-terminated ASCII string. 329 | 337 | Major number for character or block device entry. 337 | 345 | Minor number for character or block device entry. 345 | 500 | Prefix. If the pathname is too long to fit in the 100 bytes provided at the start, it can be split at any / character with the first portion going here. 500 | 512 | NUL pad.
Unused bytes are set to NUL ('\x00')s
User and group names should be used in preference to uid/gid values when they are set and the corresponding names exist on the system.
While this format is compatible with most tar readers, the format has several limitations making it unsuitable for some usages. Most notably, it cannot support sparse files, files larger than 8GiB, filenames larger than 256 characters, and non-ASCII filenames.
Reference: https://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5&format=html https://www.gnu.org/software/tar/manual/html_chapter/tar_15.html#SEC188 http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06
Implementation
static const ustar = TarFormat._internal(2);