Shell redirection operator '>&'

> name
       >! name
       >& name
       >&! name
       The file name is used as standard output.  If the file does not
       exist then it is created; if the file exists, it is  truncated,
       its previous contents being lost.

       If  the shell variable noclobber is set, then the file must not
       exist or be a character special file  (e.g.,  a  terminal  or
       `/dev/null')  or an error results.  This helps prevent acciden-
       tal destruction of files.  In this case the `!' forms  can  be
       used to suppress this check.

       The  forms  involving  `&' route the diagnostic output into the
       specified file  as  well as  the  standard  output
.   name  is
       expanded in the same way as `<' input filenames are.
原文地址:https://www.cnblogs.com/cy163/p/1201803.html