为什么递归grep显示"没有这样的文件或目录"错误？

Question

我正在贪图本地的svn目录.当我跑步时,grep -r "pattern" .我得到一些错误,如

grep:./ Data/test:没有这样的文件或目录

谁要求grep寻找不存在的文件？

---

>grep --version
grep (GNU grep) 2.10

>lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 12.04 LTS

Answer 1

默认情况下,grep不会忽略不存在或不可读的文件.您需要提供-s或--no-messages选项才能这样做.引用自man grep:

   -s, --no-messages
          Suppress  error  messages about nonexistent or unreadable files.
          Portability note: unlike GNU grep, 7th Edition Unix grep did not
          conform to POSIX, because it lacked -q and its -s option behaved
          like GNU grep's -q option.  USG-style grep also  lacked  -q  but
          its  -s  option  behaved  like GNU grep.  Portable shell scripts
          should avoid both -q and -s and  should  redirect  standard  and
          error output to /dev/null instead.  (-s is specified by POSIX.)