查找Linux系统不能登陆用户

#!/bin/sh

for PASSWD_USER in `awk -F: '{print $1}' /etc/passwd` ; do
 A=`grep -w ^$PASSWD_USER':x' /etc/passwd | awk -F: '{if($7~"false" || $7~"nologin") print "1";else print "0"}'`

 B=`grep ^"$PASSWD_USER"':' /etc/shadow | awk -F: '{if(length($2)<20) print "1";else print "0"}'`

       #echo "USER="$PASSWD_USER "A="$A "B="$B

 if [ $A -eq 1 -o $B -eq 1 ] ; then
  echo $PASSWD_USER
 fi
done

exit 0