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

6       mksquashfs - tool to create and append to squashfs filesystems
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SYNOPSIS

10       mksquashfs SOURCE [SOURCE2 ...] DESTINATION [OPTIONS]
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DESCRIPTION

14       Squashfs is a highly compressed read-only filesystem for Linux. It uses
15       zlib compression to compress both files, inodes and directories. Inodes
16       in the system are very small and all blocks are packed to minimize data
17       overhead. Block sizes greater than 4K are supported up to a maximum  of
18       64K.
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20       Squashfs is intended for general read-only filesystem use, for archival
21       use (i.e. in cases where a .tar.gz file  may  be  used),  and  in  con‐
22       strained  block device/memory systems (e.g. embedded systems) where low
23       overhead is needed.
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OPTIONS

27   Filesystem build options
28       -comp COMPRESSION
29           select  COMPRESSION  compression.   Compressors   available:   gzip
30           (default), lzma (no kernel support), lzo, lz4 and xz.
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32       -b BLOCK_SIZE
33           set data block to BLOCK_SIZE. Default 131072 bytes. Optionally K or
34           M can be used as  a  suffix  to  specify  kilobytes  or  megabytes,
35           respectively.
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37       -no-exports
38           don't make the filesystem exportable via NFS.
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40       -no-sparse
41           don't detect sparse files.
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43       -no-xattrs
44           don't store extended attributes.
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46       -xattrs
47           store extended attributes (default).
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49       -noI
50           do not compress inode table.
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52       -noD
53           do not compress data blocks.
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55       -noF
56           do not compress fragment blocks.
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58       -noX
59           do not compress extended attributes.
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61       -no-fragments
62           do not use fragments.
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64       -always-use-fragments
65           use fragment blocks for files larger than block size.
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67       -no-duplicates
68           do not perform duplicate checking.
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70       -all-root
71           make all files owned by root.
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73       -force-uid uid
74           set all file uids to uid.
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76       -force-gid gid
77           set all file gids to gid.
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79       -nopad
80           do not pad filesystem to a multiple of 4K.
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82       -keep-as-directory
83           if  one source directory is specified, create a root directory con‐
84           taining that directory, rather than the contents of the directory.
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87   Filesystem filter options
88       -p PSEUDO_DEFINITION
89           Add pseudo file definition.
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91       -pf PSEUDO_FILE
92           Add list of pseudo file definitions.
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94       -sort SORT_FILE
95           sort files according to priorities in SORT_FILE. One  file  or  dir
96           with  priority per line. Priority -32768 to 32767, default priority
97           0.
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99       -ef EXCLUDE_FILE
100           list of exclude dirs/files. One per line.
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102       -wildcards
103           Allow extended shell wildcards (globbing) to  be  used  in  exclude
104           dirs/files
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106       -regex
107           Allow POSIX regular expressions to be used in exclude dirs/files.
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110   Filesystem append options
111       -noappend
112           do not append to existing filesystem.
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114       -root-becomes NAME
115           when  appending  source  files/directories,  make the original root
116           become a subdirectory in the new  root  called  NAME,  rather  than
117           adding the new source items to the original root.
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119
120   Mksquashfs runtime options:
121       -version
122           print version, licence and copyright message.
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124       -exit-on-error
125           treat normally ignored errors as fatal.
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127       -recover NAME
128           recover filesystem data using recovery file NAME.
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130       -no-recovery
131           don't generate a recovery file.
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133       -info
134           print files written to filesystem.
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136       -no-progress
137           don't display the progress bar.
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139       -progress
140           display progress bar when using the -info option.
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142       -processors NUMBER
143           Use  NUMBER  processors.  By  default will use number of processors
144           available.
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146       -mem SIZE
147           Use SIZE physical memory. Optionally K or M can be used as a suffix
148           for kilobytes or megabytes, respectively. Default 25% of memory.
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150       -read-queue SIZE
151           Deprecated. Use -mem instead.
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153       -write-queue SIZE
154           Deprecated. Use -mem instead.
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156       -fragment-queue SIZE
157           Deprecated. Use -mem instead.
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159
160   Miscellaneous options
161       -root-owned
162           alternative name for -all-root.
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164       -noInodeCompression
165           alternative name for -noI.
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167       -noDataCompression
168           alternative name for -noD.
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170       -noFragmentCompression
171           alternative name for -noF.
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173       -noXattrCompression
174           alternative name for -noX.
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176       -Xhelp
177           print compressor options for selected compressor
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180   Compressors available and compressor specific options
181       gzip (default)
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183       -Xcompression-level compression-level
184           compression-level should be 1 .. 9 (default 9)
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186       -Xwindow-size window-size
187           window-size should be 8 .. 15 (default 15)
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189       -Xstrategy strategy1,strategy2,...,strategyN
190           Compress using strategy1,strategy2,...,strategyN in turn and choose
191           the best  compression.  Available  strategies:  default,  filtered,
192           huffman_only, run_length_encoded and fixed
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194       lzmz (no options) (no kernel support)
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196       lzo
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198       -Xalgorithm algorithm
199           Where   algorithm  is  one  of:  lzo1x_1,  lzo1x_1_11,  lzo1x_1_12,
200           lzo1x_1_15 or lzo1x_999. (default lzo1x_999)
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202       -Xcompression-level compression-level
203           compression-level should be 1 .. 9 (default 8)
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205       lz4
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207       -Xhc
208           Compress using LZ4 High Compression
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210       xz
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212       -Xbcj filter1,filter2,...,filterN
213           Compress using filter1,filter2,...,filterN in turn (in addition  to
214           no  filter),  and  choose  the best compression. Available filters:
215           x86, arm, armthumb, powerpc, sparc, ia64.
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217       -Xdict-size DICT_SIZE
218           Use DICT_SIZE as the XZ dictionary size. The dictionary size can be
219           specified  as  a  percentage  of  the block size, or as an absolute
220           value. The dictionary size must be less than or equal to the  block
221           size  and  8192 bytes or larger. It must also be storable in the xz
222           header as either 2^n or as 2^n+2^(n+1). Example dict-sizes are 75%,
223           50%, 37.5%, 25%, or 32K, 16K, 8K etc.
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225       zstd
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227       -Xcompression-level <compression-level>
228           <compression-level> should be 1 .. 22 (default 15)
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SEE ALSO

233       unsquashfs(1)
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HOMEPAGE

237       More  information  about  mksquashfs and the squashfs filesystem can be
238       found at <http://squashfs.sourceforge.net/>.
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AUTHOR

242       squashfs  was  written  by  Phillip   Lougher   <plougher@users.source‐
243       forge.net>.
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245       This   manual   page   was   written  by  Daniel  Baumann  <daniel.bau‐
246       mann@progress-technologies.net>. With some updates for 4.3 for use with
247       Fedora.
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2514.3                               2014-05-13                     MKSQUASHFS(1)
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