In Jenkins, how do builds know who requested them?

Question

I need to pass the username of the requestor of a build down to the script that is actually doing the work. Looking at the console output for a particular build, the first

Answer 1

The username isn't put in an easy-to-fetch environment variable, but you can get it using the xml (or json or python) api - as soon as you start a build, http://[jenkins-server]/job/[job-name]/[build-number]/api/xml is populated with details:

    
        
            Started by user foobar
            foobar
        
    
    true
    [...]