SQZ archives consist of one archive header and several file headers. The archive header has the following format :
OFFSET Count TYPE Description
0000h 5 char ID='HLSQZ'
0005h 1 char Version in ASCII
ID='1'
0006h 1 byte OS byte,
0 - PC-DOS / MS-DOS
1 - OS/2
2 - MVS
3 - HPFS (OS/2)
4 - Amiga
5 - Macintosh
6 - Unix
0007h 1 byte Misc. flags, bitmapped :
0 - Intel byte order / Motorola byte order
1 - Filetime in ?? / File time in DOS format
2 - No security envelope / security envelope
3-7 - reserved
After the header and each block, there is one byte denoting the type/size of the
next block :
OFFSET Count TYPE Description
0000h 1 byte Block/size specifier :
0 - End of archive
1 - Comment
2 - Password
3 - Security envelope
4-18 - reserved
>18 - normal file header,
byte value is size of header
The normal file header then has the following format :
OFFSET Count TYPE Description
0000h 1 byte Checksum of header
0001h 1 byte Flags, bitmapped :
0-3 : Compression method :
0 -
1 -
2 -
3 -
4 -
4 - Security envelope should follow
5-7 - reserved
0002h 1 dword Compressed size of file
0006h 1 dword Original file size
000Ah 1 dword Date and time of file (see table 0009)
000Eh 1 byte File attributes
000Fh 1 dword CRC-32 of file
0013h ? char Filename (see above for length)
The comment block :
OFFSET Count TYPE Description
0000h 1 word Size of uncompressed comment
0002h 1 word Size of compressed comment data
="LEN"
0004h 1 byte Flags, bitmapped, see above
0005h 1 dword CRC-32
0009h "LEN" byte Compressed comment data
The password block :
OFFSET Count TYPE Description 0000h 1 word Size of password block (=4) 0004h 1 dword CRC-32 of passwordOther blocks :
OFFSET Count TYPE Description
0000h 1 word Size of this block
="LEN"
0002h "LEN" byte Block data