$ unsquashfs -v
unsquashfs version 4.1 (2010/09/19)
copyright (C) 2010 Phillip Lougher <phillip@lougher.demon.co.uk>
$ file sysrcd.dat
sysrcd.dat: Squashfs filesystem, little endian, version 4.0, 60154231296 bytes, 69476 inodes, blocksize: 14 bytes, created: Fri Feb 22 18:25:52 1980
$ unsquashfs sysrcd.dat
Filesystem uses unknown compression, this is unsupported by this version
Decompressors available:
gzip
lzma
lzo