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diff --git a/generate-manpages/mksquashfs.h2m b/generate-manpages/mksquashfs.h2m new file mode 100644 index 0000000..8f9acaa --- /dev/null +++ b/generate-manpages/mksquashfs.h2m @@ -0,0 +1,150 @@ +[Name] +mksquashfs - tool to create and append to squashfs filesystems + +[Description] +Squashfs is a highly compressed read-only filesystem for Linux. +It uses either gzip/xz/lzo/lz4/zstd compression to compress both files, inodes +and directories. Inodes in the system are very small and all blocks are +packed to minimise data overhead. Block sizes greater than 4K are supported +up to a maximum of 1Mbytes (default block size 128K). + +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 constrained +block device/memory systems (e.g. embedded systems) where low overhead is +needed. + +[Examples] +.TP +mksquashfs DIRECTORY IMAGE.SQFS +Create a Squashfs filesystem from the contents of DIRECTORY, writing the output +to IMAGE.SQSH. Mksquashfs will use the default compressor (normally gzip), and +block size of 128 Kbytes. +.TP +mksquashfs DIRECTORY FILE1 FILE2 IMAGE.SQFS +Create a Squashfs filesystem containing DIRECTORY and FILE1 and FILE2. If +multiple sources are specified on the command line they will be combined into +a single directory. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -b 1M -comp zstd +Use a block size of 1 Mbyte and Zstandard compression to create the filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -e file1 file2 +Exclude file1 and file2 from DIRECTORY when creating filesystem. No wildcard +matching of files. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -wildcards -e "*.gz" +Exclude anything in DIRECTORY which matches the wildcard pattern "*.gz". +.TP +mksquashfs DIRECTORY IMAGE.SQFS -wildcards -e "... *.gz" +Exclude files which match the wildcard pattern "*.gz" anywhere within DIRECTORY +and its sub-directories. The initial "..." indicates the wildcard pattern is +"non-anchored" and will match anywhere. +.PP +Note: when passing wildcarded names to Mksquashfs, they should be quoted (as in +the above examples), to ensure that they are not processed by the shell. + +.SS Using pseudo file definitions +.TP +mksquashfs DIRECTORY IMAGE.SQFS -p "build_dir d 0644 0 0" +Create a directory called "build_dir" in the output filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -p "version.txt l /tmp/build/version" +Create a reference called "version.txt" to a file outside DIRECTORY, which acts +as if the file "/tmp/build/version" was copied or hard-linked into DIRECTORY +before calling Mksquashfs. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -p "date.txt f 0644 0 0 date" +Create a file called "date.txt" which holds the output (stdout) from running +the "date" command. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -p "\\"hello world\\" f 0644 0 0 date" +As above, but, showing that filenames can have spaces, if they are quoted. +The quotes need to be blackslashed to protect them from the shell. +.TP +mksquashfs - IMAGE.SQFS -p "input f 0644 root root dd if=/dev/sda1 bs=1024" -p "/ d 0644 0 0" +Create a file containing the contents of partition /dev/sda1". Ordinarily +Mksquashfs given a device, fifo, or named socket will place that special file +within the Squashfs filesystem, the above allows input from these special files +to be captured and placed in the Squashfs filesystem. Note there are no other +sources than the pseudo file, and so the command line source is "-". If there +are no other sources than pseudo files, the root (/) directory must be defined +too, as seen in this example. +.TP +unsquashfs -pf - IMAGE.SQFS | mksquashfs - NEW.SQFS -pf - +Transcode IMAGE.SQFS to NEW.SQFS by piping the pseudo file output from +Unsquashfs to Mksquashfs using stdout and stdin. This can convert from +earlier Squashfs filesystems or change compression algorithm, block size etc. +without needing to unpack into an intermediate directory or file. +.PP +Note: pseudo file definitions should be quoted (as in the above examples), to +ensure that they are passed to Mksquashfs as a single argument, and to ensure +that they are not processed by the shell. + +.SS Using extended attribute options +.TP +mksquashfs DIRECTORY IMAGE.SQFS -no-xattrs +Do not store any extended attributes in the Squashfs filesystem. Any extended +attributes in the source files will be ignored. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -xattrs-include "^user." +Filter the extended attributes in the source files, and only store extended +attributes in the user namespace in the Squashfs filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -xattrs-exclude "^user." +Filter the extended attributes in the source files, and don't store any +extended attributes in the user namespace in the Squashfs filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -xattrs-add "user.comment=hello world" +Add the extended attribute called "user.comment" with the content "hello world" +to all files and directories in the Squashfs filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -xattrs-add "user.comment=0thello world\\012" +Add the extended attribute called "user.comment" to all files and directories, +but in this case the contents of the extended attribute will be "hello world" +with a trailing newline character (012 octal). +.TP +mksquashfs DIRECTORY IMAGE.SQFS -xattrs-add "user.comment=0saGVsbG8gd29ybGQ=" +Add the extended attribute called "user.comment" to all files and directories, +where the value is given in base64 encoding, representing "hello world". +.TP +mksquashfs DIRECTORY IMAGE.SQFS -action "-xattrs-include(^user.) @ type(f)" +Filter the extended attributes but only in regular files (type f), and only +store extended attributes in the user namespace. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -p "hello_world x user.comment=0tsalve mundi\\012" +Add the extended attribute called "user.comment" to the file called +"hello_world", with the contents of the extended attribute being "salve mundi" +with a trailing newline character (012 octal). + +.SS Using Actions to not compress, change attributes etc. +.TP +mksquashfs DIRECTORY IMAGE.SQSH -action "uncompressed @ (name(*.jpg) || name(*.mpg) ) || (name(*.img) && filesize(+1G))" +Specify that any files matching the wildcards "*.jpg" and "*.mpg" should not be +compressed. Additionally, it also specifies any files matching the wildcard +"*.img" and are larger than 1 Gigabyte should be uncompressed too. This shows +test operators can be combined with logical expressions. +.TP +mksquashfs DIRECTORY IMAGE.SQSH -action "chmod(o+r)@! perm(o+r)" +If any files within DIRECTORY are not readable by "others", then make them +readable by others in the Squashfs filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQSH -action "uid(phillip)@! perm(o+r)" +As previous, match on any files which are not readable by "others", but, in +this case change the owner of the file to "phillip" in the Squashfs filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQSH -action "prune @ type(l) && ! exists" +Delete any symbolic link within DIRECTORY which points outside of DIRECTORY, +i.e. will be unresolvable in the Squashfs filesystem. +.TP +mksquashfs DIRECTORY IMAGE.SQSH -action "exclude @ depth(3)" +Create a Squashfs filesystem containing the two top most levels (contents of +DIRECTORY and immediate sub-directories), and exclude anything at level 3 or +below. +.TP +mksquashfs DIRECTORY IMAGE.SQFS -action "-xattrs-include(^user.) @ type(f)" +Filter the extended attributes but only in regular files (type f), and only +store extended attributes in the user namespace. +.PP +Note: actions should be quoted (as in the above examples), to ensure that they +are passed to Mksquashfs as a single argument, and to ensure that they are not +processed by the shell. |