单项选择题
A、POP3 B、IMAP C、SMTP D、S/MIME
A、echo The current working path is $PWD. B、echo "The current working path is $PWD." Echo hello C、echo 'The current working path is $PWD.' Echo hello D、echo "The current working path is `pwd`." E、echo The current working path is $PWD. Echo hello
A、date>>/tmp/date B、date>/tmp/date C、date 2>/tmp/date D、date &>/tmp/date