求助匹配模式n至m次的问题

qinghan1125

如下，第二个awk输出为空，原意是想数值匹配1至3次

sbmp:/tmp/ou # awk '{if($1~/[0-9]*\.[0-9]*\.[0-9]*\.[0-9]*/) print $1}' /etc/hosts
127.0.0.1
127.0.0.2
10.69.18.213
192.168.1.113

sbmp:/tmp/ou #  awk '{if($1~/[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}/) print $1}' /etc/hosts

lululau

awk  --re-interval '$1 ~ /[0-9]{1,3}\.[0-9]......./'

qinghan1125

请教我写的那个有什么问题呢

wqfhenanxc

man awk

--re-interval
              Enable the use of interval expressions in regular expression matching (see Regular , Expressionsbelow).  Interval expressions were not traditionally available in the AWK language.  The POSIX standard added them, to make awk and egrep consistent with each other.  However, their use is likely to break old AWK programs, so gawk only provides them if they are requested with this option, or when --posix is specified.

iori809

其实主要是AWK的版本问题在 POSIX之前的版本大括号不可使用。 之后就可以 了