SOS-----Net::Telnet调用cmd返回值问题

jinwh12

问：调用my @lines1 = $telnet->cmd('/sbin/ifconfig -a');为什么不能及时获取到输出呢？ 如果不sleep 2秒的话，lines1的输出 ，是在下一个print "linesps: @linesps\n"里面输出的，有大拿知道是为什么吗？

加sleep的输出：
lines1:-bash-3.1$ /sbin/ifconfig -a
eth0      Link encap:Ethernet  HWaddr 00:10:18:63 : D2 :54  
           inet addr:192.168.32.222  Bcast:192.168.32.255  Mask:255.255.255.0
不加sleep的输出：
lines1:/sbin/ifconfig -a
-bash-3.1
linesps:eth0      Link encap:Ethernet  HWaddr 00:10:18:63 : D2 : 54  
           inet addr:192.168.32.222  Bcast:192.168.32.255  Mask:255.255.255.0
部分代码如下：
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#!env perl _w
#Author: autoCreated
use Net::Telnet;
#my $telnet=Net::Telnet->new("192.168.32.222" ) ;
#$telnet->login("oracle", "oracle" ) ;

my $telnet=new Net::Telnet('Host'=>'192.168.32.222','Timeout'=>30,'Dump_Log'=>'oracletelnet.log');
$telnet->waitfor('Match'=>"/[l|L]ogin:/" ) ;
$telnet->print("oracle" ) ;
$telnet->waitfor('Match'=>"/[p|P]assword:/" ) ;
$telnet->print("oracle" ) ;
$telnet->waitfor('/type?/');
$telnet->print("vt100" ) ;
$telnet->waitfor('Match'=>"/\>|\$|#/" ) ;

sleep 2;
my @lines1 = $telnet->cmd('/sbin/ifconfig -a');
print "@lines1\n";
sleep 2;
my @linesps = $telnet->cmd('ps -ef');
print "linesps: @linesps\n";
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