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Re: Some help with dd backing up into an iso


i quoted man bzip2:
> >  As  with  compression, supplying no filenames causes decompression from
> >  standard input to standard output."

GiaThnYgeia wrote:
> ...aka screen dump?

If the standard output of bzip2 is not connected to the standard input
of another process or redirected to a file, then i'd call that a
terminal flood. Ugly text salad which may even change display settings of
your terminal window.

Standard input, standard output, and standard error output are three i/o
channels which every process on a Unix-like system has. Connecting them
to other i/o channels or redirecting them to files is a fundamental
gesture of shell programming. (Yes, the shell is a programming language,
although we often only execute single command lines.)

> > In what state is "imagefile" now ? Compressed ? Uncompressed ? Ashes ?

> Now it is at the state of being all thrown to trashcan [...]
> a new project will begin sometime next week ....

Maybe you are giving up too fast.

> I think it was that dreadful Calamares installer that came with this sid
> distro that locks onto the disk and prevents ovewriting.

I deem this unlikely. Your Linux was up and had control. Our problem
is not about overwriting but about finding a directory path under which
we can read the files of the USB stick partition.

> But the usb was so hard locked that gparted would erase its partition,

So you interspersed some other experiments ? That might be entertaining
but also confusing.

> > is it reported as two lines:

> No it is all connected line [...]

> > The reason why i ask is that i wonder from where xorriso has this
> > strange two-line path.  It would be explainable if you had given it to
> > xorriso command "-map".

> So are you saying the problem may lie in the name length that xorriso
> can't handle?

No. The name length should not be an obstacle until it reaches limits
of the X/Open system specification (255 characters per name, 1024 per path).

The problem is rather that xorriso gets to see a file path which does
not lead to an existing file. Either this name stems from the program
arguments of the run (i.e. is given after -map) or it stems from
following a symbolic link, which tells a wrong target path.
In the first case, the operator i(i.e. you) is to blame. In the second
case, some automat installed confusing links.

> the question I have is if this is ....part1 where is the other part/s?

"part" shall mean "partition". I just wanted to keep the name short.

> > New approach to get to a mount point of the stick:

> xorriso : UPDATE : 116500 files added in 28 seconds
> xorriso : FAILURE : Cannot open as source directory: '/media/user/sid/lost+found'
> ...
> xorriso : aborting : -abort_on 'FAILURE' encountered 'FAILURE'

We got some progress now.
The new problem is the fact that xorriso (and possibly other user
processes, too) cannot read the content of

So why does this file make trouble ? IIRC, it is a directory which
holds files that were found orphaned during filesystem checks.
Please report the output of

  ls -ld /media/user/sid/lost+found

(I will have to investigate why xorriso tells no further reason for
 being unable to read the directory's file list.)


Whatever, this is a local filesystem problem which we may try to
circumvent by omitting the offending file object.

   xorriso \
   -for_backup \
   -outdev usb_part1.iso \
   -not_paths /media/user/sid/lost+found -- \
   -map /media/user/sid /

The xorriso command -not_paths takes one or more file paths which then
get excluded from the backup. The word "--" marks the end of this path list,
so that the next word "-map" is then interpreted as next xorriso command.

Let's see how far we will get with this try.

If more unreadable "lost+found" directories show up, you may ban the
name from being backed up when found under any path:

   xorriso \
   -for_backup \
   -outdev usb_part1.iso \
   -not_leaf lost+found \
   -map /media/user/sid /

Other than -not_paths, -not_leaf takes exactly one parameter. So no end
makr "--" is necessary.

Have a nice day :)