awk 控制语句if-else

语法：

一、if (条件){语句}[else 语句]    单分支

二、if (条件){语句}else if（ 条件）{语句}    多分支

示例：

1、[root@localhost ~]# awk -F: '{if($3>=1000)print $1,$3}'  /etc/passwd
zjz 1000
zjz1 1001

2、[root@localhost ~]# awk -F: '{if($NF=="/bin/bash")print $1}' /etc/passwd
root
zjz
zjz1

3、[root@localhost ~]# awk -F: '{if($3>=1000){print "Common user:%s
",$1}else {print "root or Sysuser:%s
",$1}}'   /etc/passwd 
root or Sysuser:%s
 sshd
root or Sysuser:%s
 apache
Common user:%s
 zjz
Common user:%s
 zjz1

4、[root@localhost ~]# df -hT |awk -F% '/^/dev/sda1/{print $1}'|awk '$NF>=10{print $1,$6}'
/dev/sda1 13

5、[root@localhost ~]# awk 'BEGIN{test=20;if(test>90){print "very good"}else if (test>60){print "good"}else {print "no pass"} }'
no pass