[^abc] 匹配 表达式用于查找任何不在方括号之间的字符

node2:/root#perl aa.pl
$1 === nginxd
node2:/root#cat aa.pl 
my $a='nginxdd';
if ($a =~/(nginx[^abc])/){print "$1 === $1
";};
node2:/root#perl aa.pl
$1 === nginxd


node2:/root#cat aa.pl
my $a='nginxdd';
if ($a =~/(nginx[^abc]+)/){print "$1 === $1
";};
node2:/root#perl aa.pl
$1 === nginxdd