From a77651ef8a1d6283734062690569e35679850f58 Mon Sep 17 00:00:00 2001 From: Ralph Ronnquist Date: Sun, 25 Jun 2023 13:36:04 +1000 Subject: [PATCH 1/1] Editorial cleanup. Docuemnting -dump. --- fusefile.8 | 75 ++++++++++++++++++++++++++++++------------------------ 1 file changed, 42 insertions(+), 33 deletions(-) diff --git a/fusefile.8 b/fusefile.8 index 2b116a9..6af36f4 100644 --- a/fusefile.8 +++ b/fusefile.8 @@ -6,26 +6,22 @@ fusefile, fusedisk \- FUSE file mount for combining file fragments .SH SYNOPSIS .B fusefile \fR[\fIfuse-opts\fR] \fBmountpoint\fR \fR[\fIoverlay\fR] \fIfilename/from-to\fR ... .br +.B fusefile \fB-dump\fR \fR[\fIfuse-opts\fR] \fBmountpoint\fR \fR[\fIoverlay\fR] \fIfilename/from-to\fR ... +.br .B fusedisk \fR[\fIfuse-opts\fR] \fBmountpoint\fR \fR[\fIoverlay\fR] \fIfilename/from-to\fR ... .SH DESCRIPTION -\fBfusefile\fR is a FUSE file mount that presents a series of -fragments of other files as a contiguous concatenation. It bind mounts -a driver on top of the file mountpoint to present the nominated file -fragments as a single, contiguous file. \fBfusefile\fR accepts -over-writing on the fused file (i.e. the mountpoint) which gets -distributed accordingly to the fragments, but it cannot change size; -any writing thus merely replaces content without truncating fragments. -All fragment files are held open while \fBfusefile\fR is active. +\fBfusefile\fR is a FUSE \fIfile mount\fR that presents a series of +fragments of other files as a contiguous concatenation. Technically it +bind mounts a driver on top of the filename mountpoint to provide +access to the given file fragments as if in a single, contiguous file. -\fBfusedisk\fR is a helper script to set up a \fBfusefile\fR as a -block device (via \fIfuseblk\fR) by using the device mapper -(\fBdmsetup\fR) to manage an empty block device mapping where content -is handled at the mountpoint via \fBfusefile\fR. (Note that the same -thing may be done with the device manager directly, but then all -fragments need to be in sectors of N*512 bytes. With \fBfusedisk\fR -only the fused file as a whole is "clipped" at N*512 bytes) +\fBfusefile\fR accepts over-writing on the fused file (i.e. the +mountpoint) which gets distributed accordingly to the fragments. But +neither the fused file nor the fragments can change size; any writing +thus merely over-writes content without truncating fragments. All +fragment files are held open while \fBfusefile\fR is active. By using the optional \fB-overlay:\fIfilename\fR argument between the mount point and the fragments, an overlay file may be set up. The @@ -35,10 +31,22 @@ any new written fused file regions followed by meta data to distinguish between new, written content and old content that comes from the fragments. -The option \fB-dump\fR together with an overlay fusefile setup will -print the current overlay table to standard output rather than -establishing a fusefile mount. The table is printed as the series of -fusefile fragments using the argments as given. +The option \fB-dump\fR as first argument together with a fusefile +setup will print the setup to standard output rather than establishing +a fusefile mount. This is of most use with a prior overlay setup, +where then the printout includes the portions of updates that have +been captured in the overlay. The printout is the series of fusefile +fragment argments to give in order to intersperse the captured overlay +portions according to the overlay table. + +\fBfusedisk\fR is a helper script to set up a \fBfusefile\fR as a +block device (via \fIfuseblk\fR) by using the device mapper +(\fBdmsetup\fR) to manage an empty block device mapping where content +is handled at the mountpoint via \fBfusefile\fR. (Note that the same +thing may be done with the device manager directly, but then all +fragments need to be in sectors of N*512 bytes whereas with +\fBfusedisk\fR, only the fused file as a whole is "clipped" at nearest +N*512 bytes below actual size) .SH FRAGMENT ARGUMENTS @@ -84,7 +92,15 @@ This section enumerates the most interesting options to use with \fBfuesfile\fR. See "man fuse" and "man mount" for more options. .TP -\fI-oallow_other\fB +\fB-dump\fR + +The \fB-dump\fR "option" tells \fBfusefile\fR to print out the +applicable fragment sequence for the current setup, including the +overlay table, if any. The printout is done instead of setting up a +mount point. + +.TP +\fB-o\fIallow_other\fB The fuse option \fI-oallow_other\fR is needed for sharing the fused file with other users who otherwise will not have access to it @@ -92,25 +108,18 @@ file with other users who otherwise will not have access to it \fI/etc/fuse.conf\fR. .TP -\fI-ononempty\fR +\fB-o\fInonempty\fR The fuse option \fI-ononempty\fR may need to be used when reusing an existing file as mountpoint. .TP -\fI-ouid=...\fR, \fI-ogid=...\fR, - -The mount options \fI-ouid=...\fR and \fI-ogid=...\fR, where \fI...\fR - is a user or group id respectively, are useful for root when using - \fBfusedisk\fR and thereby give user or group ownership for the mount - to the nominated user or group. - -.TP -\fI-dump\fR +\fB-o\fIuid=...\fR and \fB-o\fIgid=...\fR, -This "mount option" triggers fusefil to, instead of setting up a mount -point, print out the applicable fusefile fragment sequence for the -current setup as way of presenting the overlay table. +These mount options, where \fI...\fR is a user or group id +respectively, are useful for root when using \fBfusedisk\fR and +thereby give user or group ownership for the mount to the nominated +user or group. .SH EXAMPLES This section illustrates uses of \fBfusefile\fR. -- 2.39.2