4 This project implements a "fuse" device to mount as a single file that
5 is a concatenation of fragments of one or more files. The fused file
6 allows overwriting the parts files, but not changing their sizes, and
7 only for parts files that are writable upon first access.
9 FUSE file mount for combining file fragments.
14 *fusefile* [ _fuse options_ ] *mountpoint* +_filename_/from:to+ ...
19 *fusefile* is FUSE file mount that presents a series of fragments of
20 other files as a contiguous concatenation. It bind mounts a driver on
21 top of the file mountpoint to present the nominated file fragments as
22 a single, contiguous file.
24 The fragment arguments include the filename of a source file, and
25 optionally start and end byte positions. All in all there five
28 * __filename__ include all of the file.
30 * __filename/__ include all of the file named with "/" in the pathname. This case requires a final "/", since the last "/" separates the filename from the position details.
32 * __filename/from__ include the file from the given start position, to end.
34 * __filename/-to__ include the file from beginning to the given end position (not included).
36 * __filename/from:to__ include the file from the given start position, up to the given end position (not included).
40 .Insert file "y" into file "x" at position 1200:
42 $ fusefile -ononempty x x/:1200 y x/1200:
44 That mount will shadow the original file "x", and presents the
47 .Make file y be a swap of the beginning and end of file "x", at position 2442:
49 $ fusefile y x/2442: x/:2442
51 .Replace a partition in an image file with a different file
53 $ partx -oNR,START,SECTORS disk.raw
58 # Replace partition 2 of 409600 sectors from 2099200 with
59 # the file "insert.fat" clipped to 409600 sectors.
60 $ fusefile -ononempty disk.raw \
61 disk.raw/0:$(( 2099200*512 )) \
62 insert.fat/0:$(( 409600*512 )) \
63 disk.raw/$(( (2099200+409600)*512 )):
68 Note that **fusefile** opens the nominated source file(s) before bind
69 mounting. With the fuse option __-ononempty__ it will bind over an
70 non-empty file, which may be useful. The source file descriptors
71 remain open, but the source fragments are not recomputed. If a source
72 file changes or reduces in size "behind" the fused file, then anything
75 If the mountpoint file doesn't exist, then **fusefile** creates it and
76 removes it when unmounted.
78 Unmounting is done with "fusermount -u __fused file__" as usual.
82 Ralph Rönnquist <ralph.ronnquist@gmail.com>