☰

shopt -s extglob 的用途是什么

tag-icon • tag-icon command-line bash
shopt -s extglob 的用途是什么

我想删除目录中除一个文件之外的所有文件。我找到了解决方案这里。此解决方案使用此命令：

shopt -s extglob

我想知道这个命令到底起什么作用，一些后端知识。

答案1

简单来说，通配符是指模式匹配。Bash 使用简单的通配符，例如，echo l*它扩展为当前目录中以字母 开头的文件列表l。当然，正如你所猜测的，它很简单，功能有限。

输入extglob。正如您所猜到的，它代表extended globbing。此选项允许更高级的模式匹配。从man bash：

extglob If set, the extended pattern matching features described
        above under Pathname Expansion are enabled.

在此之前：

If the extglob shell option is enabled using the shopt builtin, several
extended pattern matching operators are recognized.  In  the  following
description, a pattern-list is a list of one or more patterns separated
by a |.  Composite patterns may be formed using  one  or  more  of  the
following sub-patterns:

      ?(pattern-list)
             Matches zero or one occurrence of the given patterns
      *(pattern-list)
             Matches zero or more occurrences of the given patterns
      +(pattern-list)
             Matches one or more occurrences of the given patterns
      @(pattern-list)
             Matches one of the given patterns
      !(pattern-list)
             Matches anything except one of the given patterns

有很多方法extglob可以使用它。Linux 杂志和格雷格的维基。

相关内容