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mksquashfs(1) [centos man page]

MKSQUASHFS(1)					      create and append squashfs filesystems					     MKSQUASHFS(1)

mksquashfs - tool to create and append to squashfs filesystems SYNOPSIS
Squashfs is a highly compressed read-only filesystem for Linux. It uses zlib compression to compress both files, inodes and directories. Inodes in the system are very small and all blocks are packed to minimize data overhead. Block sizes greater than 4K are supported up to a maximum of 64K. Squashfs is intended for general read-only filesystem use, for archival use (i.e. in cases where a .tar.gz file may be used), and in con- strained block device/memory systems (e.g. embedded systems) where low overhead is needed. OPTIONS
Filesystem build options -comp COMPRESSION select COMPRESSION compression. Compressors available: gzip (default), lzo, xz. -b BLOCK_SIZE set data block to BLOCK_SIZE. Default 131072 bytes. -no-exports don't make the filesystem exportable via NFS. -no-sparse don't detect sparse files. -no-xattrs don't store extended attributes. -xattrs store extended attributes (default). -noI do not compress inode table. -noD do not compress data blocks. -noF do not compress fragment blocks. -noX do not compress extended attributes. -no-fragments do not use fragments. -always-use-fragments use fragment blocks for files larger than block size. -no-duplicates do not perform duplicate checking. -all-root make all files owned by root. -force-uid uid set all file uids to uid. -force-gid gid set all file gids to gid. -nopad do not pad filesystem to a multiple of 4K. -keep-as-directory if one source directory is specified, create a root directory containing that directory, rather than the contents of the directory. Filesystem filter options -p PSEUDO_DEFINITION Add pseudo file definition. -pf PSEUDO_FILE Add list of pseudo file definitions. -sort SORT_FILE sort files according to priorities in SORT_FILE. One file or dir with priority per line. Priority -32768 to 32767, default priority 0. -ef EXCLUDE_FILE list of exclude dirs/files. One per line. -wildcards Allow extended shell wildcards (globbing) to be used in exclude dirs/files -regex Allow POSIX regular expressions to be used in exclude dirs/files. Filesystem append options -noappend do not append to existing filesystem. -root-becomes NAME when appending source files/directories, make the original root become a subdirectory in the new root called NAME, rather than adding the new source items to the original root. Mksquashfs runtime options: -version print version, licence and copyright message. -recover NAME recover filesystem data using recovery file NAME. -no-recovery don't generate a recovery file. -info print files written to filesystem. -no-progress don't display the progress bar. -processors NUMBER Use NUMBER processors. By default will use number of processors available. -read-queue SIZE Set input queue to SIZE Mbytes. Default 64 Mbytes. -write-queue SIZE Set output queue to SIZE Mbytes. Default 512 Mbytes. -fragment-queue SIZE Set fragment queue to SIZE Mbytes. Default 64 Mbytes. Miscellaneous options -root-owned alternative name for -all-root. -noInodeCompression alternative name for -noI. -noDataCompression alternative name for -noD. -noFragmentCompression alternative name for -noF. -noXattrCompression alternative name for -noX. Compressors available and compressor specific options gzip (no options) (default) lzo (no options) xz -Xbcj filter1,filter2,...,filterN Compress using filter1,filter2,...,filterN in turn (in addition to no filter), and choose the best compression. Available filters: x86, arm, armthumb, powerpc, sparc, ia64. -Xdict-size DICT_SIZE Use DICT_SIZE as the XZ dictionary size. The dictionary size can be specified as a percentage of the block size, or as an absolute value. The dictionary size must be less than or equal to the block size and 8192 bytes or larger. It must also be storable in the xz header as either 2^n or as 2^n+2^(n+1). Example dict-sizes are 75%, 50%, 37.5%, 25%, or 32K, 16K, 8K etc. SEE ALSO
unsquashfs(1) HOMEPAGE
More information about mksquashfs and the squashfs filesystem can be found at <>. AUTHOR
squashfs was written by Phillip Lougher <>. This manual page was written by Daniel Baumann <>. 4.2 2012-06-30 MKSQUASHFS(1)
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