如何让grep跳过搜索目录？

Question

当我做grep foo *时，我收到了许多警告：

grep: dir1: Is a directory
grep: dir2: Is a directory
grep: dir3: Is a directory
grep: dir4: Is a directory
grep: dir5: Is a directory

我宁愿只看到结果而不是这些警告。

Answer 1

grep foo * --directories=skip将跳过像常规文件一样的grepping目录。

根据手册页：

 -d action, --directories=action
         Specify the demanded action for directories.  It is `read' by default, which means that the directories
         are read in the same manner as normal files.  Other possible values are `skip' to silently ignore the
         directories, and `recurse' to read them recursively, which has the same effect as the -R and -r option.

此外，grep foo * -s也会做同样令人满意的事情。

 -s, --no-messages
         Silent mode.  Nonexistent and unreadable files are ignored (i.e. their error messages are suppressed).