From 8b51499900e125a55dcdc425d29550b98a8064b4 Mon Sep 17 00:00:00 2001 From: Jan Sucan Date: Sat, 18 Jan 2025 07:57:57 +0100 Subject: Initial implementation of diff file format v2 --- README.md | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) (limited to 'README.md') diff --git a/README.md b/README.md index 33a71b6..7c88f34 100644 --- a/README.md +++ b/README.md @@ -10,17 +10,15 @@ This simple utility was created to reduce size of backup images of disk partitions. It is intended to be used in conjunction with ```dd``` or similar -utility. The primary concern is safe operation, so ```diff-dd``` performs many -checks of the input and output files. For example, the differential image file -is read twice when restoring it. Because of that, it is slower. +utility. ## Synopsis > diff-dd help -> diff-dd backup [-S SECTOR_SIZE] [-B BUFFER_SIZE] -i INFILE -b BASEFILE -o OUTFILE +> diff-dd backup [-B BUFFER_SIZE] -i INFILE -b BASEFILE -o OUTFILE -> diff-dd restore [-S SECTOR_SIZE] [-B BUFFER_SIZE] -d DIFFFILE -o OUTFILE +> diff-dd restore [-B BUFFER_SIZE] -d DIFFFILE -o OUTFILE ## Backup @@ -31,24 +29,20 @@ exist. Differential backup is created with: The ```INFILE``` is a path to the file to backup differentially, the ```BASEFILE``` is the full image, and the ```OUTFILE``` is the file to -which only the changed sectors of the ```INFILE```, compared to the -```BASEFILE```, and their offsets will be saved. +which the changed data of the ```INFILE```, compared to the +```BASEFILE```, their offsets, and sizes will be saved. ## Restore -The restoration means application of the changed sectors saved in the +The restoration means application of the changed data saved in the ```DIFFFILE```, which is the differential image, to the ```OUTFILE```: > diff-dd restore -d DIFFFILE -o OUTFILE ## Options -```-S``` sets the sector size by which the files will be processed -(default is 512 B). It can be used to control granularity of -differential backup. - -```-B``` sets the size of the buffer for the sectors of the input and -output file (default is 4 MiB). The input data is always buffered. The +```-B``` sets the size of the buffer for the data of the input and +output files (default is 4 MiB). The input data is always buffered. The output data are buffered only in backup mode. ## Example -- cgit v1.2.3