root@xyf-laptop:~# perl -e ' print getpwuid($<);'
root$6$J0bTOS1H$lnxARf6GOL5rPmGIuYR4IkFBbANmrTeSaIj8BrCehOkftUB2xjPbxqqPLJlzd2C6p4OGCvyIZ6kzhQZ1vRO5d000root/root/bin/bashroot@xyf-laptop:~# 
root@xyf-laptop:~# 
root@xyf-laptop:~# perl -e ' $a = getpwuid($<); print $a;'
rootroot@xyf-laptop:~#