rm可以用来删除文件和文件夹。
rm --help
Usage: rm [OPTION]... FILE...Remove (unlink) the FILE(s).
-f, --force ignore nonexistent files, never prompt（提示）
-i prompt before every removal
-I prompt once before removing more than three files, or
when removing recursively. Less intrusive than -i,
while still giving protection against most mistakes
--interactive[=WHEN] prompt according to WHEN: never, once (-I), or
always (-i). Without WHEN, prompt always
--one-file-system when removing a hierarchy recursively, skip any
directory that is on a file system different from
that of the corresponding command line argument
--no-preserve-root do not treat `/' specially
--preserve-root do not remove `/' (default)
-r, -R, --recursive remove directories and their contents recursively（递归地）
-v, --verbose explain what is being done
--help display this help and exit
--version output version information and exit
By default, rm does not remove directories. Use the --recursive (-r or -R)
option to remove each listed directory, too, along with all of its contents.
To remove a file whose name starts with a `-', for example `-foo',
use one of these commands:
rm -- -foo
rm ./-foo
Note that if you use rm to remove a file, it is usually possible to recover
the contents of that file. If you want more assurance that the contents are
truly unrecoverable, consider using shred.
Report rm bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
For complete documentation, run: info coreutils 'rm invocation'>
