grep -o 选项使用时的一个问题。

yjh777

[0-9]*  0个或多个，只匹配0个。
[0-9]\+ 1个或多个，却匹配多个。

[root@test9 root]# echo sdgasdg124asdf | grep -o '[0-9]*'
[root@test9 root]# echo sdgasdg124asdf | grep -o '[0-9]\+'
124
[root@test9 root]# echo sdgasdg124asdf | grep -o '[0-9]*'
[root@test9 root]# grep --version
grep (GNU grep) 2.5.1

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[ 本帖最后由 yjh777 于 2006-12-5 17:58 编辑 ]