Updated description of -cut_out

This commit is contained in:
Thomas Schmitt 2008-03-11 13:09:56 +00:00
parent 2309710729
commit 47c72f3059
1 changed files with 32 additions and 9 deletions

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@ -2,7 +2,7 @@
.\" First parameter, NAME, should be all caps
.\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
.\" other parameters are allowed: see man(7), man(1)
.TH XORRISO 1 "February 21, 2008"
.TH XORRISO 1 "March, 11, 2008"
.\" Please adjust this date whenever revising the manpage.
.\"
.\" Some roff macros, for reference:
@ -587,16 +587,13 @@ addressing: Its semantics is similar to -add and thus avoids the pitfalls
inherited from cp -r behavior. Its syntax resembles cp, though.
.TP
\fB\-cut_out\fR disk_path byte_offset byte_count iso_rr_path
WARNING: This option is fewly tested.
Especially it is not coordinated with -compare_r and -update_r.
.br
Map a byte interval of a regular disk file into a regular file in the ISO
image.
This may be necessary if the disk file is larger than a single media, or if
it exceeds the traditional limit of 2 GiB - 2 kiB for old operating systems,
or the limit of 4 GiB - 2 kiB for newer ones.
.br
The clumsy remedy for this limit is to backup file pieces and to concatenate
A clumsy remedy for this limit is to backup file pieces and to concatenate
them at restore time. A well tested chopping size is 2047m.
It is permissible to request a higher byte_count than available. The
resulting file will be truncated to the correct size of a final piece.
@ -604,11 +601,37 @@ To request a byte_offset higher than available yields no file in
the ISO image but a SORRY event.
E.g:
.br
-cut_out disk_file 0 2047m iso_rr_part1
-cut_out /my/disk/file 0 2047m \\
.br
-cut_out disk_file 2047m 2047m iso_rr_part2
/file/part_1_of_3_at_0_with_2047m_of_5753194821 \\
.br
-cut_out disk_file 4094m 2047m iso_rr_part3
-cut_out /my/disk/file 2047m 2047m \\
.br
/file/part_2_of_3_at_2047m_with_2047m_of_5753194821 \\
.br
-cut_out /my/disk/file 4094m 2047m \\
.br
/file/part_3_of_3_at_4094m_with_2047m_of_5753194821
.br
-cut_out is not yet coordinated with -compare_r and -update_r.
But the names of the part files in this example already follow a
future convention by which xorriso will be able to recognize
file parts and process them accordingly:
.br
A disk file gets mapped to a ISO directory. Its split parts
have names which describe the splitting by 5 numbers which are separated
by some text:
.br
part_number, total_parts, byte_offset, byte_count, disk_path_size
.br
Scaling characters like "m" or "k" are taken into respect and may
serve as separators as well. All digits are interpreted as decimal,
even if leading zeros are present.
.br
Not all parts have to be present on the same media. But those parts
which are present have to sit in the same directory. No other files
are allowed in there. Parts have to be disjoint. Their numbers have
to be plausible. byte_count must be valid as -cut_out argument.
.TP
\fB\-rm\fR iso_rr_path [***]
Delete the given files from the ISO image.
@ -1820,7 +1843,7 @@ versions.
Theoretical limits are higher but in practice the media deteriorate more early.
It might also be that your operating system has a session limit with mount.
Always have a blank media ready to perform a full backup in case the update
attempt fails.
attempt fails. An overview of sessions is given by option -toc.
.br
If you have enough re-useable media for a round-robin scheme then better do
full backups with blank media each time. Blanking can be achieved by