version update

[rrq/fusefile.git] / fusefile.8

diff --git a/fusefile.8 b/fusefile.8
index b4bd50d314f7b3504677285e7660e1fbc17da885..183a362bce8c42bff4b27764ba01a4930625b37e 100644 (file)
--- a/fusefile.8
+++ b/fusefile.8
@@ -4,7 +4,7 @@
 fusefile \- FUSE file mount for combining file fragments
 
 .SH SYNOPSIS
 fusefile \- FUSE file mount for combining file fragments
 
 .SH SYNOPSIS

-.B fusefile \fR[fuse options\fR] \fBmountpoint\fR \fIfilename/from-to\fR ...
+.B fusefile \fR[\fIfuse-opts\fR] \fBmountpoint\fR \fR[\fIoverlay\fR] \fIfilename/from-to\fR ...

 
 .SH DESCRIPTION
 
 
 .SH DESCRIPTION
 


@@ -15,6 +15,13 @@ as a single, contiguous file. It accepts over-writing on the fused
 file which gets distributed accordingly to the fragments, but cannot
 change size.
 
 file which gets distributed accordingly to the fragments, but cannot
 change size.
 

+An optional overlay file is declared with the "-overlay:filename"
+argument between the mount point and the fragments. This file is then
+set up as an overlay for capturing writes to the fused file. The
+overlay file will contain the written fused file regions, followed by
+meta data to distinguish between written content and "holes" (where
+content comes from the fused fragments).
+

 The fragment arguments include the filename of a source file, and
 optionally start and end byte positions. All in all there five
 variations:
 The fragment arguments include the filename of a source file, and
 optionally start and end byte positions. All in all there five
 variations:


@@ -66,6 +73,14 @@ position 2442:
 \fB$ fusefile y x/2442: x/:2442\fR
 .RE
 
 \fB$ fusefile y x/2442: x/:2442\fR
 .RE
 

+Protect raw disk image file with an overlay:
+.RS
+\fB# fusefile -ononempty disk.raw -overlay:today disk.raw
+.RE
+By this set up, the overlay file, "today", will protect the disk image
+file, "disk.raw" from changes, and also override the pathname
+"disk.raw" to be the fused file.
+

 .SH NOTES
 
 Note that \fBfusefile\fR opens the nominated source file or files
 .SH NOTES
 
 Note that \fBfusefile\fR opens the nominated source file or files


@@ -78,6 +93,10 @@ If a source is reduced in size, access will be inconsistent.
 If the mountpoint file doesn't exist, then \fBfusefile\fR creates it,
 and removes it when unmounted.
 
 If the mountpoint file doesn't exist, then \fBfusefile\fR creates it,
 and removes it when unmounted.
 

+Using an overlay file makes the fused file writable regardless of the
+fused fragemnts with the overlay file containing any changes to the
+original. The overlay file is reusable for subsequent fusing of the
+same fragments for reconstructing a prior session.

 
 .SH AUTHOR
 
 
 .SH AUTHOR