bytie - convinient byte stream manipulation

Previews

TODO Pictues here

Instruction

bytie allows to add, delete, replace and cut bytes of an input byte stream or from a file. Surely, one is able to do the same thing with dd, however I find its command line interface a bit cumbersome at times.

Installation

Building from source

Clone the repository

> git clone https://github.com/awidegreen/bytie.git
> cd bytie

Build and install via cargo. Note that you need a fairly recent rust version.

> cargo install --path .

Via Cargo

NOTE: NOT YET PUBLISHED

Install bytie from crates.io.

> cargo install bytie

Usage

Examples

Add a string at a certain position.

> echo "foobar" | bytie add -v WORLD 3
fooWORLDbar

Replace a string at a certain position, where replacement data comes from STDIN.

# create test file
> echo "foobar" > test

> echo -n "FOO" | bytie test replace 0
FOObar

Cut/extract bytes from input.

# note positional argument (range)
> echo "foobar" | bytie cut 1:4
ooba

Delete bytes from input.

# note positional argument (length)
> echo "foobar" | bytie delete 1+3
fr

General bytie options

bytie has several general command line options which are valid and usable for all subcommands:

• -b|--blocksize: By default bytie reads from the input with a blocksize of 1024 bytes, this can be changed using this option.
• -o|--out: Use this option if the result should be written to a file instead of STDOUT.
• -i|--in-place: Write byte manipulation output to the provided input <file>. This only works if <file> has been specified.
• <file> (optional): The input file which will act as a data source for the subcommand operation.

NOTE: Based on the specification of the <file> parameter, bytie will decide where the input data originates from. Meaning, if <file> is omitted, STDIN will be used as input stream for the respective subcommand action. In such cases, subcommands like replace and add will not be able take input data for the replacement/insertion from STDIN.

For more information consult byties help (-h|--help).

Subcommands

bytie provides the following subcommand to fulfill different use cases:

NOTE:: bytie positional indicators (start, end) start from index 0, so the 'b' in foobar is at index 4.

cut - Extract data from input

alias: extract

Can be used to cut/extract certain bytes from an input stream by providing the start and end position (or a length, see position parameter description below).

Cut in this context means that only the specified range will remain in the output. In contrast to delete which will remove bytes from the input.

delete - Remove data from input

alias: remove

Deletes a range of bytes from the provided input stream. In contrast to cut where the specified range will be the output. As for cut a positional parameter need to be specified (see below).

add - Insert data to input

alias: insert

Inserts provided data to the input data at the specified start position (begin). The data to be inserted/added can originate from STDIN or the subcommands --value parameter (STDIN is only possible if source data is not provided via STDIN).

replace - Replace data from input

alias: substitute

Replaces provided data at the input data at the specified start position (begin). The data to be replaced can originate from STDIN or the subcommands --value parameter (STDIN is only possible if source data is not provided via STDIN).

bytie will always write the complete replacement data, meaning that the output data might be longer than the input.

Positional parameter

The cut and delete subcommands require a position as an argument. This has the following format:

<begin>         Begin to the end of input
<begin>:<end>   Begin to end (exclusive), requires <end> > <begin>
                Example: 'foobar', 0:2 == 'fo' or 3:5 == 'ba'
<begin>:=<end>  Begin to end (inclusive), requires <end> > <begin>
                Example: 'foobar', 0:=2 == 'foo' or 3:=5 == 'bar'
<begin>+<count> Begin plus <count> (exclusive), requires <count> > 0.
                The length includes the begin position: 0+10 is 10 bytes, from 0..9 (same as 0:9)

Possible feature extensions

• Implement line instead of byte mode. All subcommand should behave the same but instead of working and manipulating bytes, lines should be used. This might be useful if one just want to see a specific line of a file - which otherwise could be achieved with sed if one remembers the syntax.
• allow multiple operations in one executions

License

Copyright (c) 2020 - Armin Widegreen

bytie is licensed under the 3-Clause BSD License (3-Clause BSD or https://opensource.org/licenses/BSD-3-Clause)