ZCK\_DELTA\_SIZE(1) General Commands Manual ZCK\_DELTA\_SIZE(1)

# [NAME](#NAME)

`zck_delta_size` — calculate the differences between two zchunk files

# [SYNOPSIS](#SYNOPSIS)

`zck_delta_size` \[`-v` | `--verbose`] `file1` `file2`

`zck_delta_size` `-`? | `--help` | `--usage` | `--version`

# [DESCRIPTION](#DESCRIPTION)

The `zck_delta_size` utility examines two zchunk compressed files and determines how similar they are: how many chunks are the same between the files, so that tools like e.g. [rsync(1)](/man/enterprise-packages/zchunk/rsync.1) or [zckdl(1)](/man/enterprise-packages/zchunk/zckdl.1) could only transfer the small parts that differ instead of the full files. This is especially useful for structured files that have been compressed using the [zck(1)](/man/enterprise-packages/zchunk/zck.1) tool's `-s` (`--split`) option.

The `zck_delta_size` utility accepts the following optional arguments:

[`-v`](#v), `--verbose`

Verbose operation; display some diagnostic output.

`-`?, `--help`

Display program usage information and exit.

[`--usage`](#usage)

Display brief program usage information and exit.

[`--version`](#version)

Display program version information and exit.

# [EXIT STATUS](#EXIT_STATUS)

The `zck_delta_size` utility exits 0 on success, and >0 if an error occurs.

# [EXAMPLES](#EXAMPLES)

Examine two zchunk files:

`zck_delta_size doc1.txt.zck doc2.txt.zck`

# [SEE ALSO](#SEE_ALSO)

[unzck(1)](/man/enterprise-packages/zchunk/unzck.1), [zck(1)](/man/enterprise-packages/zchunk/zck.1), [zck\_gen\_zdict(1)](/man/enterprise-packages/zchunk/zck_gen_zdict.1), [zck\_read\_header(1)](/man/enterprise-packages/zchunk/zck_read_header.1), [zckdl(1)](/man/enterprise-packages/zchunk/zckdl.1)

# [AUTHOR](#AUTHOR)

The `zck_delta_size` utility was written by Jonathan Dieter ⟨jdieter@gmail.com⟩. This manual page stub was written by Peter Pentchev ⟨roam@ringlet.net⟩.

May 31, 2020 Linux 4.19.0-gvisor

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Document: zck_delta_size(1) from zchunk 1.5.5-r2 (Chainguard OS)
Source: https://github.com/zchunk/zchunk.git