grep root pass 查看pass中含有root字符的结果
grep ^root pass 查看开头为root的结果
grep root$ pass 结尾为root的字符
grep -i root pass 限制开为为大写的R的结果
grep -E "root|ROOT" pass 显示为root或者ROOT的结果(注意。使用-E时,是有两个条件)
grep -E "^root|root$" pass -v
grep -E '\<...t' pass
grep -E "\<....t\>" pass
显示三个字符的内容
grep -E "\<[[:alpha:]]{3}\>|[[:digit:]]{1,}" westos
grep ^root pass 查看开头为root的结果
grep root$ pass 结尾为root的字符
grep -i root pass 限制开为为大写的R的结果
grep -E "root|ROOT" pass 显示为root或者ROOT的结果(注意。使用-E时,是有两个条件)
grep -E "^root|root$" pass -v
grep -E '\<...t' pass
grep -E "\<....t\>" pass
显示三个字符的内容
grep -E "\<[[:alpha:]]{3}\>|[[:digit:]]{1,}" westos