jenkins中 ${WORKSPACE}含义

cp ${WORKSPACE}/Delivery_System_0908/environment.properties ${WORKSPACE}/allure-results
${WORKSPACE} = /var/jenkins_home/workspace/songqin0926
cp /var/jenkins_home/workspace/songqin0926/Delivery_System_0908/environment.properties /var/jenkins_home/workspace/songqin0926/allure-results