Auto‑Embed Build Version Info in Embedded Software with Git and date

1. Software Management Challenges

Large‑scale software projects often have long cycles, many temporary builds, and numerous bugs caused by numerous contributors with varying skill levels, leading to version‑tracking problems such as missing test builds and performance‑impacting disputes.

2. Simplified Version Number

For clarity, the article proposes a minimal version identifier that only prints the release timestamp, illustrated by the following image:

3. Principle

A dedicated header file sw_version.h stores the version macro. The main program includes this header and prints the macro at startup. During compilation, a script mk.sh updates the header with the current date, so the built executable always carries the latest version information.

#define SW_VERSION "2024-09-09-7"

The header can be updated either by a C program or directly via the date command; the article demonstrates the latter.

4. date Command Options

The Linux date utility can display or set system time. Common options used in this tutorial include: --help: show help --version: show version -u: display UTC time -d: perform date arithmetic

Key usage for this guide is displaying the current date/time in a custom format:

# date '+%Y-%m-%d %H:%M:%S'

Result example (image):

5. Bash Script Example

#!/bin/bash

str_front=#define SW_VERSION
quotation="\""
version_file=sw_version.h

rm $version_file

echo $str_front $quotation$(date '+%Y-%m-%d-%H')$quotation >> $version_file

Explanation:

Define str_front to hold the macro prefix.

Define quotation to hold a double‑quote character.

Set version_file to the header name.

Remove any existing header.

Append a line like #define SW_VERSION "2024-09-09-7" generated by date to the header.

6. Result

Running the script produces a sw_version.h containing the updated version macro, which can be compiled into the application. The output screenshots (shown below) confirm the header content and the printed version at program start.

Developers can adapt the script and format to meet their own version‑numbering conventions and integrate it into existing build pipelines.