Regex grep后跟一系列数字的字符串

我有这个日志：

2014-09-24 10:07:44 +0000 severity=INFO, Completed 200 OK in 955ms (Views: 566.4ms | ActiveRecord: 246.9ms)
2014-09-24 10:06:53 +0000 severity=INFO, Completed 404 Not Found in 13ms (Views: 12.0ms | ActiveRecord: 0.0ms)
2014-09-24 10:06:43 +0000 severity=INFO, Completed 500 OK in 939ms (Views: 547.8ms | ActiveRecord: 253.0ms)
2014-09-24 10:05:44 +0000 severity=INFO, Completed 501 OK in 721ms (Views: 495.1ms | ActiveRecord: 198.2ms)
2014-09-24 10:04:43 +0000 severity=INFO, Completed 200 OK in 997ms (Views: 592.6ms | ActiveRecord: 238.4ms)
2014-09-24 10:03:43 +0000 severity=INFO, Completed 401 OK in 983ms (Views: 584.8ms | ActiveRecord: 237.0ms)

我想使用正则表达式执行grep，以便获得包含不同类型错误的所有行。 例如：

所有客户端错误：已完成4*

2014-09-24 10:06:53 +0000 severity=INFO, Completed 404 Not Found in 13ms (Views: 12.0ms | ActiveRecord: 0.0ms)
2014-09-24 10:03:43 +0000 severity=INFO, Completed 401 OK in 983ms (Views: 584.8ms | ActiveRecord: 237.0ms)

所有服务器错误：已完成5次*

2014-09-24 10:06:43 +0000 severity=INFO, Completed 500 OK in 939ms (Views: 547.8ms | ActiveRecord: 253.0ms)
2014-09-24 10:05:44 +0000 severity=INFO, Completed 501 OK in 721ms (Views: 495.1ms | ActiveRecord: 198.2ms)

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您有什么建议吗？

您可以使用以下正则表达式进行搜索：

grep 'Completed [0-9]' error.log

或者，要仅获取以

4

和

5

开头的状态代码，请使用：

grep 'Completed [45]' error.log

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这两个命令都搜索日志文件中的给定模式。第一种模式是：

'Completed[0-9]

，意思是文本

已完成

，后跟任何数字。第二个模式是

完成

，后面是数字

4或5。