gnu constant
GNU header format.
The GNU header format is older than the USTAR and PAX standards and is not compatible with them. The GNU format supports arbitrary file sizes, filenames of arbitrary encoding and length, sparse files, and other features.
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 " to indicate that this is the GNU format. 263 | 265 | Version. " \x00" 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 | 357 | Last Access time of file, number of seconds from epoch, stored as an octal number in ASCII. 357 | 369 | Last Changed time of file, number of seconds from epoch, stored as an octal number in ASCII. 369 | 381 | Offset - not used. 381 | 385 | Longnames - deprecated 385 | 386 | Unused. 386 | 482 | Sparse data - 4 sets of (offset, numbytes) stored as octal numbers in ASCII. 482 | 483 | isExtended - if this field is non-zero, this header is followed by additional sparse records, which are in the same format as above. 483 | 495 | Binary representation of the file's complete size, inclusive of the sparse data. 495 | 512 | NUL pad.
It is recommended that PAX be chosen over GNU unless the target application can only parse GNU formatted archives.
Reference: https://www.gnu.org/software/tar/manual/html_node/Standard.html
Implementation
static const gnu = TarFormat._internal(8);