In Jenkins, how to checkout a project into a specific directory (using GIT)

node{
    sh"""
    mkdir('foo')
    """
    dir ('foo') {
        git branch: "<ref spec>", changelog: false, poll: false, url: '<clone url>'
        ......
    }
}

from : https://stackoverflow.com/questions/9767919/in-jenkins-how-to-checkout-a-project-into-a-specific-directory-using-git

passing variable to bash script in a jenkins pipeline job

def UNIQUE = sh(returnStdout: true, script: 'uuidgen').trim()

from : https://stackoverflow.com/questions/40323490/passing-variable-to-bash-script-in-a-jenkins-pipeline-job