Files on cramfs file systems are zlib-compressed one page at a time
to allow random read access. The metadata is not compressed, but is
expressed in a terse representation that is more space-efficient than
conventional file systems.
The file system is intentionally read-only to simplify its design;
random write access for compressed files is difficult to implement.
cramfs ships with a utility (mkcramfs) to pack files into new cramfs
File sizes are limited to less than 16 MB.
Maximum file system size is a little under 272 MB. (The last file on
the file system must begin before the 256 MB block, but can extend
-v Enable verbose messaging.
-E Treat all warnings as errors, which are reflected as command
Use defined block size, which has to be divisible by page
Use defined file system edition number in superblock.
-N big, little, host
Use defined endianness. Value defaults to host.
Insert a file to cramfs file system.
Set name of the cramfs file system.
-p Pad by 512 bytes for boot code.
-s This option is ignored. Originally the -s turned on directory
-z Make explicit holes. Use of this option will require 2.3.39
kernel, or newer.
-V Display version information and exit.
-h Display help and exit.
This page is part of the util-linux (a random collection of Linux
utilities) project. Information about the project can be found at
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have a
bug report for this manual page, send it to
firstname.lastname@example.org. This page was obtained from the
project's upstream Git repository
2017-03-13. If you discover any rendering problems in this HTML ver‐
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information in this COLOPHON (which is not part of the original man‐
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util-linux April 2013 MKFS.CRAMFS(8)