page 572, in Class Method Reading and Writing, line 4 : commend instead of command
is interpreted as a command. In that case, the commend is executed in a subprocess and
-----> ^^^^^^^
+++++ paragraph 3, line 4 : missing for ?
... The keyword options are the same as File.open. ...
-----> ^
Usually, in such situations for is used :
… encoding options available for File.open.
The optional arguments are the same as for File.new.