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-rw-r--r--doc/Makemodule.am3
-rw-r--r--doc/gensquashfs.1201
-rw-r--r--doc/rdsquashfs.199
-rw-r--r--doc/sqfs2tar.193
-rw-r--r--doc/sqfsdiff.172
-rw-r--r--doc/tar2sqfs.1154
6 files changed, 0 insertions, 622 deletions
diff --git a/doc/Makemodule.am b/doc/Makemodule.am
index 9963467..f6870c8 100644
--- a/doc/Makemodule.am
+++ b/doc/Makemodule.am
@@ -1,4 +1 @@
-dist_man1_MANS += doc/gensquashfs.1 doc/rdsquashfs.1 doc/sqfs2tar.1
-dist_man1_MANS += doc/tar2sqfs.1 doc/sqfsdiff.1
-
EXTRA_DIST += doc/format.txt doc/parallelism.txt doc/mainpage.dox
diff --git a/doc/gensquashfs.1 b/doc/gensquashfs.1
deleted file mode 100644
index 9ef4ee8..0000000
--- a/doc/gensquashfs.1
+++ /dev/null
@@ -1,201 +0,0 @@
-.TH GENSQUASHFS "1" "June 2019" "generate squashfs images" "User Commands"
-.SH NAME
-gensquashfs \- generate squashfs images
-.SH SYNOPSIS
-.B gensquashfs
-[\fI\,OPTIONS\/\fR] <squashfs-file>\/\fR
-.SH DESCRIPTION
-Generate a SquashFS image.
-.SH OPTIONS
-.TP
-\fB\-\-pack\-file\fR, \fB\-F\fR <file>
-Use a \fBgen_init_cpio\fR style description file. The file format is specified
-below. If \fB\-\-pack\-dir\fR is used, input file paths are relative to the
-pack directory, otherwise they are relative to the directory the pack file
-is in.
-.TP
-\fB\-\-pack\-dir\fR, \fB\-D\fR <directory>
-If \fB\-\-pack\-file\fR is used, this is the root path relative to which to
-read files. If no pack file is specified, pack the contents of the given
-directory into a SquashFS image. The directory becomes the root of the file
-system.
-.TP
-\fB\-\-compressor\fR, \fB\-c\fR <name>
-Select the compressor to use.
-Run \fBgensquashfs \-\-help\fR to get a list of all available compressors
-and the default selection.
-.TP
-\fB\-\-comp\-extra\fR, \fB\-X\fR <options>
-A comma separated list of extra options for the selected compressor. Specify
-\fBhelp\fR to get a list of available options.
-.TP
-\fB\-\-num\-jobs\fR, \fB\-j\fR <count>
-If libsquashfs was compiled with a built in thread pool based, parallel data
-compressor, this option can be used to set the number of compressor
-threads. If not set, the default is the number of available CPU cores.
-.TP
-\fB\-\-queue\-backlog\fR, \fB\-Q\fR <count>
-Maximum number of data blocks in the thread worker queue before the packer
-starts waiting for the block processors to catch up. Higher values result
-in higher memory consumption. Defaults to 10 times the number of workers.
-.TP
-\fB\-\-block\-size\fR, \fB\-b\fR <size>
-Block size to use for Squashfs image.
-Defaults to 131072.
-.TP
-\fB\-\-dev\-block\-size\fR, \fB\-B\fR <size>
-Device block size to padd the image to.
-Defaults to 4096.
-.TP
-\fB\-\-keep\-time\fR, \fB\-k\fR
-When using \fB\-\-pack\-dir\fR only, use the timestamps from the input files
-instead of setting defaults on all input paths. The root inode and the
-modification time on the SquashFS image itself will still be set to defaults.
-.TP
-\fB\-\-one\-file\-system\fR, \fB\-o\fR
-When using \fB\-\-pack\-dir\fR only, stay in the local filesystem and do not
-cross mount points.
-.TP
-\fB\-\-defaults\fR, \fB\-d\fR <options>
-A comma separated list of default values for
-implicitly created directories.
-The following values can be set:
-.TS
-tab(;) allbox;
-l l
-l l
-l l
-l l
-l l
-rd.
-\fBOption\fR;\fBDefault\fR
-uid=<value>;0
-gid=<value>;0
-mode=<value>;0755
-mtime=<value>;\fB$SOURCE\_DATE\_EPOCH\fR if set, 0 otherwise
-.TE
-.TP
-.TP
-\fB\-\-set\-uid\fR, \fB\-u\fR <number>
-Force the owners user ID for ALL inodes to this value, no matter what the pack
-file or directory entries actually specify.
-.TP
-\fB\-\-set\-gid\fR, \fB\-g\fR <number>
-Force the owners group ID for ALL inodes to this value, no matter what the pack
-file or directory entries actually specify.
-.TP
-\fB\-\-all\-root\fR
-A short hand for `\-\-set\-uid 0 \-\-set\-gid 0`.
-.TP
-\fB\-\-selinux\fR, \fB\-s\fR <file>
-If built with SELinux support, use the given SELinux label file to add context
-labels to the elements packed into the SquashFS image.
-.TP
-\fB\-\-exportable\fR, \fB\-e\fR
-Generate an export table for NFS support.
-.TP
-\fB\-\-no\-tail\-packing\fR, \fB\-T\fR
-Do not perform tail end packing on files that are larger than the specified
-block size.
-.TP
-\fB\-\-force\fR, \fB\-f\fR
-Overwrite the output file if it exists.
-.TP
-\fB\-\-quiet\fR, \fB\-q\fR
-Do not print out progress reports.
-.TP
-\fB\-\-help\fR, \fB\-h\fR
-Print help text and exit.
-.TP
-\fB\-\-version\fR, \fB\-V\fR
-Print version information and exit.
-.SH INPUT FILE FORMAT
-The input file contains a simple, newline separated list that describe the
-files to be included in the squashfs image:
-.PP
-.in +4n
-.nf
-# a comment
-file <path> <mode> <uid> <gid> [<location>]
-dir <path> <mode> <uid> <gid>
-nod <path> <mode> <uid> <gid> <dev_type> <maj> <min>
-slink <path> <mode> <uid> <gid> <target>
-link <path> <dummy> <dummy> <dummy> <target>
-pipe <path> <mode> <uid> <gid>
-sock <path> <mode> <uid> <gid>
-.fi
-.in
-
-.TS
-tab(;) allbox;
-l l
-l l
-l l
-l l
-l l
-l l
-l l
-l l
-l l
-rd.
-<path>;T{
-Absolute path of the entry in the image. Can be put in quotes
-if some components contain spaces.
-T}
-<location>;T{
-Optional location of the input file. Can be specified relative to either the
-description file or the pack directory. If omitted, the image path is used
-as a relative path.
-T}
-<target>;Symlink or hardlink target.
-<mode>;Mode/permissions of the entry.
-<uid>;Numeric user id.
-<gid>;Numeric group id.
-<dev_type>;Device type (b=block, c=character).
-<maj>;Major number of a device special file.
-<min>;Minor number of a device special file.
-.TE
-
-.PP
-Example:
-.PP
-.in +4n
-.nf
-# A simple squashfs image
-dir /dev 0755 0 0
-nod /dev/console 0600 0 0 c 5 1
-dir /root 0700 0 0
-dir /sbin 0755 0 0
-
-# Add a file. Input is relative to pack dir or listing path
-file /sbin/init 0755 0 0 ../init/sbin/init
-
-# Read from ./bin/bash relative to pack dir or listing path
-# /bin is created implicitly with default attributes.
-file /bin/bash 0755 0 0
-
-# file name with a space in it and a "special" name
-file "/opt/my app/\\"special\\"/data" 0600 0 0
-.fi
-.in
-.SH ENVIRONMENT
-If the command line switch \fB\-\-defaults\fR is not used or no default mtime
-is specified, the value of the environment variable \fBSOURCE\_DATE\_EPOCH\fR
-is used for all file and filesystem timestamps.
-
-If \fBSOURCE\_DATE\_EPOCH\fR is not set, not a parsable number or it is out of
-range, the timestamps default to 0.
-
-Environment variables are only used if no explicit command line switches
-are set. Explicit command line switches are always preferred over the
-environment variables.
-.SH SEE ALSO
-rdsquashfs(1), tar2sqfs(1)
-.SH AUTHOR
-Written by David Oberhollenzer.
-.SH COPYRIGHT
-Copyright \(co 2019 David Oberhollenzer
-License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
-.br
-This is free software: you are free to change and redistribute it.
-There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/rdsquashfs.1 b/doc/rdsquashfs.1
deleted file mode 100644
index a5e1d77..0000000
--- a/doc/rdsquashfs.1
+++ /dev/null
@@ -1,99 +0,0 @@
-.TH RDSQUASHFS "1" "May 2019" "inspect SquashFS filesystems" "User Commands"
-.SH NAME
-rdsquashfs \- tool to examine or uncompress SquashFS filesystems
-.SH SYNOPSIS
-.B rdsquashfs
-[\fI\,OPTIONS\/\fR] \fI\,<squashfs-file>\/\fR
-.SH DESCRIPTION
-View or extract the contents of a squashfs image.
-.PP
-The following options can be used to specify what operation to perform. One
-of those has to be present:
-.TP
-\fB\-\-list\fR, \fB\-l\fR <path>
-Produce a directory listing similar to \fBls \-l\fR for a given path in
-the SquashFS image.
-.TP
-\fB\-\-cat\fR, \fB\-c\fR <path>
-If the specified path is a regular file in the image, extract it and dump
-its contents to stdout.
-.TP
-\fB\-\-xattr\fR, \fB\-x\fR <path>
-If the inode that the specified path resolves to has extended attributes, dump
-them as key value pairs to stdout.
-.TP
-\fB\-\-unpack\-path\fR, \fB\-u\fR <path>
-Unpack the specified sub directory from the image. To unpack everything,
-simply specify /.
-.TP
-\fB\-\-describe\fR, \fB\-d\fR
-Produce a file listing from the image compatible with the format consumed by
-gensquashfs.
-.PP
-The following options can be used to control the behaviour of the specified
-operation:
-.TP
-\fB\-\-unpack\-root\fR, \fB\-p\fR <path>
-If used with \fB\-\-unpack\-path\fR, this is where the
-data is unpacked to. If used with \fB\-\-describe\fR, this
-is used as a prefix for the input path of
-regular files.
-.TP
-\fB\-\-no\-dev\fR, \fB\-D\fR
-Skip device special files when parsing the filesystem tree.
-.TP
-\fB\-\-no\-sock\fR, \fB\-S\fR
-Skip socket files when parsing the filesystem tree.
-.TP
-\fB\-\-no\-fifo\fR, \fB\-F\fR
-Skip named pipes when parsing the filesystem tree.
-.TP
-\fB\-\-no\-slink\fR, \fB\-L\fR
-Skip symbolic links when parsing the filesystem tree.
-.TP
-\fB\-\-no\-empty\-dir\fR, \fB\-E\fR
-Skip empty directories, including ones that are empty after applying
-the above rules.
-.PP
-The following options are specific to unpacking files from a SquashFS image
-to disk:
-.TP
-\fB\-\-no\-sparse\fR, \fB\-Z\fR
-Do not create sparse files. Always unpack sparse files by
-writing blocks of zeros to disk.
-.TP
-\fB\-\-set\-xattr\fR, \fB\-X\fR
-Set the extended attributes from the SquashFS image.
-.TP
-\fB\-\-set\-times\fR, \fB\-T\fR
-Set the create and modify timestamps of the file to the mtime
-from the SquashFS image.
-.TP
-\fB\-\-chmod\fR, \fB\-C\fR
-Change permission flags of unpacked files to
-those stored in the SquashFS image.
-.TP
-\fB\-\-chown\fR, \fB\-O\fR
-Change ownership of unpacked files to the
-UID/GID set in the SquashFS image.
-.TP
-\fB\-\-quiet\fR, \fB\-q\fR
-Do not print out progress while unpacking.
-.PP
-Other options:
-.TP
-\fB\-\-help\fR, \fB\-h\fR
-Print help text and exit.
-.TP
-\fB\-\-version\fR, \fB\-V\fR
-Print version information and exit.
-.SH SEE ALSO
-gensquashfs(1), sqfs2tar(1), sqfsdiff(1)
-.SH AUTHOR
-Written by David Oberhollenzer.
-.SH COPYRIGHT
-Copyright \(co 2019 David Oberhollenzer
-License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
-.br
-This is free software: you are free to change and redistribute it.
-There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/sqfs2tar.1 b/doc/sqfs2tar.1
deleted file mode 100644
index 0fc69f6..0000000
--- a/doc/sqfs2tar.1
+++ /dev/null
@@ -1,93 +0,0 @@
-.TH SQFS2TAR "1" "June 2019" "sqfs2tar" "User Commands"
-.SH NAME
-sqfs2tar \- turn a SquashFS image into a tar archive
-.SH SYNOPSIS
-.B sqfs2tar
-[\fI\,OPTIONS\/\fR...] \fI\,<sqfsfile>\/\fR
-.SH DESCRIPTION
-Quickly and painlessly turn a SquashFS filesystem image into a tar archive
-that can then be examined and processed by any tool that can work on tar
-archives. The resulting archive is written to stdout.
-.PP
-Possible options:
-.TP
-\fB\-\-root\-becomes\fR, \fB\-r\fR <dir>
-Prefix all paths in the tarball with the given directory name and add an
-entry for this directory that receives all meta data (permissions, ownership,
-extended attributes, et cetera) of the root inode.
-
-The special value \fB.\fR can be used since many tar archivers themselves pack
-the attributes of the root directory that way and naturally support this.
-
-If this option is not used, all meta data from the root inode IS LOST!
-.TP
-\fB\-\-subdir\fR, \fB\-d\fR <dir>
-Unpack the given sub directory instead of the filesystem root. Can be specified
-more than once to select multiple directories. If only one is specified, it
-becomes the new root of the archive filesystem tree.
-.TP
-\fB\-\-keep\-as\-dir\fR, \fB\-k\fR
-If \fB\-\-subdir\fR is used only once, don't make the subdir the archive root,
-instead keep it as prefix for all unpacked files. Using \fB\-\-subdir\fR more
-than once implies \fB\-\-keep\-as\-dir\fR.
-.TP
-\fB\-\-no\-xattr\fR, \fB\-X\fR
-Discard extended attributes from the SquashFS image. The default behavior is
-to copy all xattrs attached to SquashFS inodes into the resulting tar archive.
-.TP
-\fB\-\-no\-hard\-links\fR, \fB\-L\fR
-Normally, sqfs2tar runs hard link detection and generates hard links for
-entries that refer to the same inode. If this flag is set, hard link
-detection is not performed and duplicate data records are generated
-instead.
-.TP
-\fB\-\-no\-skip\fR, \fB\-s\fR
-Abort if a file cannot be stored in a tar archive. For instance, the tar format
-does not support socket files, but SquashFS does. The default behaviour of
-\fBsqfs2tar\fR is to emit a warning to stderr and skip the entry. If this flag
-is set, processing is aborted and \fBsqfs2tar\fR exits with an error status.
-.TP
-\fB\-\-help\fR, \fB\-h\fR
-Print help text and exit.
-.TP
-\fB\-\-version\fR, \fB\-V\fR
-Print version information and exit.
-.SH COMPATIBILITY
-The output format is pre-POSIX ustar using GNU extensions where necessary.
-Experimentation determined that this is most widely supported by activeley
-used tar implementations (besides GNU tar), even more than the newer POSIX
-format with PAX extensions.
-
-If any file or directory is encountered that cannot be converted, it is
-skipped and a warning is written to stderr. Unless the \fB\-\-no\-skip\fR
-option is set, which aborts processing if a file cannot be converted.
-
-This mainly affects socket files which are supported by SquashFS but not by
-POSIX tar, GNU tar or PAX.
-
-Since the tar format contains a sequence of files with absolute names, it has
-no direct concept of a tree or an unnamed root node. Consequently, meta data
-from the SquashFS root inode is lost, unless the \fB\-\-root\-becomes\fR option
-is used.
-.SH EXAMPLES
-Turn a SquashFS image into a tar archive:
-.IP
-sqfs2tar rootfs.sqfs > rootfs.tar
-.TP
-Turn a SquashFS image into a gzip'ed tar archive:
-.IP
-sqfs2tar rootfs.sqfs | gzip > rootfs.tar.gz
-.TP
-Turn a SquashFS image into an LZMA2 compressed tar archive:
-.IP
-sqfs2tar rootfs.sqfs | xz > rootfs.tar.xz
-.SH SEE ALSO
-rdsquashfs(1), tar2sqfs(1)
-.SH AUTHOR
-Written by David Oberhollenzer.
-.SH COPYRIGHT
-Copyright \(co 2019 David Oberhollenzer
-License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
-.br
-This is free software: you are free to change and redistribute it.
-There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/sqfsdiff.1 b/doc/sqfsdiff.1
deleted file mode 100644
index c0ee550..0000000
--- a/doc/sqfsdiff.1
+++ /dev/null
@@ -1,72 +0,0 @@
-.TH SQFSDIFF "1" "August 2019" "sqfsdiff" "User Commands"
-.SH NAME
-sqfsdiff \- compare two squashfs images by contents and metadata
-.SH SYNOPSIS
-.B sqfsdiff
-[\fI\,OPTIONS\/\fR...] \-\-old \fI\,<first>\fR \-\-new \fI\,<second>\/\fR
-.SH DESCRIPTION
-Compare two squashfs images. In contrast to doing a direct diff of the
-images, this actually parses the filesystems and generates a more
-meaningful difference report.
-.PP
-If only contents are compared, any differences in packed file layout,
-ordering, compression, inode meta data and so on is ignored and the two
-images are considered equal if each directory contains the same entries,
-symlink with the same paths have the same targets, device nodes the same
-device number and files the same size and contents.
-.PP
-A report of any difference is printed to stdout. The exit status is similar
-that of diff(1): 0 means equal, 1 means different, 2 means problem.
-.PP
-Possible options:
-.TP
-\fB\-\-old\fR, \fB\-a\fR <first>
-Specify the first filesystem image or source directory, relativ to which the
-changes are evaluated.
-.TP
-\fB\-\-new\fR, \fB\-b\fR <second>
-Specify the second filesystem image to source directory to compare to the
-first one.
-.TP
-\fB\-\-no\-contents\fR, \fB\-C\fR
-Do not compare file contents.
-.TP
-\fB\-\-no\-owner\fR, \fB\-O\fR
-Do not compare file owners.
-.TP
-\fB\-\-no\-permissions\fR, \fB\-P\fR
-Do not compare permission bits.
-.TP
-\fB\-\-timestamps\fR, \fB\-T\fR
-Compare file timestamps.
-.TP
-\fB\-\-inode\-num\fR, \fB\-I\fR
-Compare inode numbers of all files.
-.TP
-\fB\-\-super\fR, \fB\-S\fR
-Also compare meta data in super blocks.
-.TP
-\fB\-\-extract\fR, \fB\-e\fR <path>
-Extract files that exist in both images but have different contents to the
-specified directory. Contents of the first image end up in a sub directory
-named \fBold\fR and the contents of the second image in a sub directory
-named \fBnew\fR.
-.TP
-\fB\-\-help\fR, \fB\-h\fR
-Print help text and exit.
-.TP
-\fB\-\-version\fR, \fB\-V\fR
-Print version information and exit.
-.SH EXIT STATUS
-The exit status is similar that of diff(1): 0 means equal, 1 means different,
-2 means problem.
-.SH SEE ALSO
-rdsquashfs(1), sqfs2tar(1)
-.SH AUTHOR
-Written by David Oberhollenzer.
-.SH COPYRIGHT
-Copyright \(co 2019 David Oberhollenzer et al
-License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
-.br
-This is free software: you are free to change and redistribute it.
-There is NO WARRANTY, to the extent permitted by law.
diff --git a/doc/tar2sqfs.1 b/doc/tar2sqfs.1
deleted file mode 100644
index da344ec..0000000
--- a/doc/tar2sqfs.1
+++ /dev/null
@@ -1,154 +0,0 @@
-.TH TAR2SQFS "1" "June 2019" "tar2sqfs" "User Commands"
-.SH NAME
-tar2sqfs \- create a SquashFS image from a tar archive
-.SH SYNOPSIS
-.B tar2sqfs
-[\fI\,OPTIONS\/\fR...] \fI\,<sqfsfile>\/\fR
-.SH DESCRIPTION
-Quickly and painlessly turn a tar ball into a SquashFS filesystem image.
-.PP
-Possible options:
-.TP
-\fB\-\-root\-becomes\fR, \fB\-r\fR <dir>
-If set, only pack entries that are underneath the specified directory. The
-prefix is stripped and the meta data for the directory itself is copied to the
-root inode (i.e. the ownership, permissions, extended attributes,
-modification time).
-
-If this option is not set, tar2sqfs implicitly treats \fB./\fR or absolute
-paths this way, i.e. if the archive contains an entry for \fB./\fR, it becomes
-the root node and the prefix is stripped from all paths (and similar for
-absolute paths and \fB/\fR).
-.TP
-\fB\-\-compressor\fR, \fB\-c\fR <name>
-Select the compressor to use.
-Run \fBtar2sqfs \-\-help\fR to get a list of all available compressors
-and the default selection.
-.TP
-\fB\-\-comp\-extra\fR, \fB\-X\fR <options>
-A comma separated list of extra options for the selected compressor. Specify
-\fBhelp\fR to get a list of available options.
-.TP
-\fB\-\-num\-jobs\fR, \fB\-j\fR <count>
-If libsquashfs was compiled with a thread pool based, parallel data
-compressor, this option can be used to set the number of compressor
-threads. If not set, the default is the number of available CPU cores.
-.TP
-\fB\-\-queue\-backlog\fR, \fB\-Q\fR <count>
-Maximum number of data blocks in the thread worker queue before the packer
-starts waiting for the block processors to catch up. Higher values result
-in higher memory consumption. Defaults to 10 times the number of workers.
-.TP
-\fB\-\-block\-size\fR, \fB\-b\fR <size>
-Block size to use for SquashFS image.
-Defaults to 131072.
-.TP
-\fB\-\-dev\-block\-size\fR, \fB\-B\fR <size>
-Device block size to padd the image to.
-Defaults to 4096.
-.TP
-\fB\-\-defaults\fR, \fB\-d\fR <options>
-A comma separated list of default values for
-implicitly created directories.
-The following values can be set:
-.TS
-tab(;) allbox;
-l l
-l l
-l l
-l l
-l l
-rd.
-\fBOption\fR;\fBDefault\fR
-uid=<value>;0
-gid=<value>;0
-mode=<value>;0755
-mtime=<value>;\fB$SOURCE\_DATE\_EPOCH\fR if set, 0 otherwise
-.TE
-.TP
-.TP
-\fB\-\-no\-keep\-time\fR, \fB\-k\fR
-Replace the time stamps from the tar archive with default time stamps for all
-entries.
-
-The default behavior is to preserve the time stamps from the archive to the
-extent possible (SquashFS has second resolution and 32 bit time stamps; tar can
-use extensions to specify much larger timestamps with arbitrary precision). The
-root inode (unless \fB\-\-root\-becomes\fR is used) and the modification time on
-the SquashFS image itself will still be set to defaults.
-.TP
-\fB\-\-no\-xattr\fR, \fB\-x\fR
-Do not copy extended attributes from archive. Default behaviour is to copy all
-extended attributes and skip the ones that cannot be encoded in SquashFS.
-.TP
-\fB\-\-no\-skip\fR, \fB\-s\fR
-Abort if a tar record cannot be read instead of skipping it.
-.TP
-\fB\-\-exportable\fR, \fB\-e\fR
-Generate an export table for NFS support.
-.TP
-\fB\-\-no\-tail\-packing\fR, \fB\-T\fR
-Do not perform tail end packing on files that are larger than the
-specified block size.
-.TP
-\fB\-\-force\fR, \fB\-f\fR
-Overwrite the output file if it exists.
-.TP
-\fB\-\-quiet\fR, \fB\-q\fR
-Do not print out progress reports.
-.TP
-\fB\-\-help\fR, \fB\-h\fR
-Print help text and exit.
-.TP
-\fB\-\-version\fR, \fB\-V\fR
-Print version information and exit.
-.SH COMPATIBILITY
-Currently the program can process v7 format, pre-POSIX ustar, POSIX tar and GNU
-tar archives. PAX extension headers are also supported. Global PAX headers are
-ignored.
-
-The support for GNU tar is limited to commonly used subset (i.e. some legacy
-extensions that GNU tar itself no longer generates are not supported; neither
-are mutli volume archives).
-
-Extended attributes are supported through the SCHILY.xattr PAX extension
-(favoured by GNU tar and star) or through the LIBARCHIVE.xattr PAX extension.
-
-If any unsupported section or extended attribute key is encountered in an
-archive, a warning message is written to stderr. If the \fB\-\-no\-skip\fR
-option is set, processing aborts. By default, unknown sections and unsupported
-extended attributes are simply skipped after issuing a warning.
-.SH ENVIRONMENT
-If the command line switch \fB\-\-defaults\fR is not used or no default mtime
-is specified, the value of the environment variable \fBSOURCE\_DATE\_EPOCH\fR
-is used for all file and filesystem timestamps.
-
-If \fBSOURCE\_DATE\_EPOCH\fR is not set, not a parsable number or it is out of
-range, the timestamps default to 0.
-
-Environment variables are only used if no explicit command line switches
-are set. Explicit command line switches are always preferred over the
-environment variables.
-.SH EXAMPLES
-.TP
-Turn an uncompressed tar archive into a SquashFS image:
-.IP
-tar2sqfs rootfs.sqfs < rootfs.tar
-.TP
-Turn a gzip'ed tar archive into a SquashFS image:
-.IP
-zcat rootfs.tar.gz | tar2sqfs rootfs.sqfs
-.TP
-Turn an LZMA2 compressed tar archive into a SquashFS image:
-.IP
-xzcat rootfs.tar.xz | tar2sqfs rootfs.sqfs
-.SH SEE ALSO
-gensquashfs(1), rdsquashfs(1), sqfs2tar(1)
-.SH AUTHOR
-Written by David Oberhollenzer.
-.SH COPYRIGHT
-Copyright \(co 2019 David Oberhollenzer
-License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
-.br
-This is free software: you are free to change and redistribute it.
-There is NO WARRANTY, to the extent permitted by law.