Get/Set general purpose bit flag for entry
Remarks
General purpose bit flag
Bit 0: If set, indicates the file is encrypted
Bit 1-2 Only used for compression type 6 Imploding, and 8, 9 deflating
Imploding:
Bit 1 if set indicates an 8K sliding dictionary was used. If clear a 4k dictionary was used
Bit 2 if set indicates 3 Shannon-Fanno trees were used to encode the sliding dictionary, 2 otherwise
Deflating:
Bit 2 Bit 1
0 0 Normal compression was used
0 1 Maximum compression was used
1 0 Fast compression was used
1 1 Super fast compression was used
Bit 3: If set, the fields crc-32, compressed size and uncompressed size are were not able to be written during zip file creation The correct values are held in a data descriptor immediately following the compressed data.
Bit 4: Reserved for use by PKZIP for enhanced deflating
Bit 5: If set indicates the file contains compressed patch data
Bit 6: If set indicates strong encryption was used.
Bit 7-15: Unused or reserved