chmod只能修改权限，不能更改所有者，更改所有者的命令是：
复制内容到剪贴板
代码:
#chown user:group /directory/file在线手册man是这样定义：
复制内容到剪贴板
代码:
CHOWN(1) User Commands CHOWN(1)
NAME
chown - change file owner and group
SYNOPSIS
chown [OPTION]... [OWNER][:[GROUP]] FILE...
chown [OPTION]... --reference=RFILE FILE...
DESCRIPTION
This manual page documents the GNU version of chown. chown changes the
user and/or group ownership of each given file. If only an owner (a
user name or numeric user ID) is given, that user is made the owner of
each given file, and the files' group is not changed. If the owner is
followed by a colon and a group name (or numeric group ID), with no
spaces between them, the group ownership of the files is changed as
well. If a colon but no group name follows the user name, that user is
made the owner of the files and the group of the files is changed to
that user's login group. If the colon and group are given, but the
owner is omitted, only the group of the files is changed; in this case,
chown performs the same function as chgrp. If only a colon is given,
or if the entire operand is empty, neither the owner nor the group is
changed.
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