Question

I would like to have a variable (or #define) in C++ source that will increment each time I use Qt Creator to build source code. Is there any way I can do this, perhaps some Qt Creator plugin or similar? If there is a way to do it if I use “make” on command line to build?

Answer 1

In your .pro file, you can create a variable that contains the results of a command-line program. You can then use that to create a define.

BUILDNO = $$(command_to_get_the_build_number)
DEFINES += BUILD=$${BUILDNO}

If you just want a simple incrementing number, you could use a pretty simple script:

#!/bin/bash
number=`cat build_number`
let number += 1
echo "$number" | tee build_number #<-- output and save the number back to file

I should note that this would cause the build number to increment every time you build, and also increment if you try to build but it fails. A better way is to get a build number based on the state of the code, and many version control tools can get you a text string for that, if not a number.