Data Capture Issue using expect in tcl - expect

Question

I have one doubt in expect. I want to store the result of command in a string variable. Can anyone tell me what is the mistake in my code? It is not working. I have used expect_out(buffer) but its not working.
#!/usr/bin/expect
package require Expect
set Argu1 [lindex $argv 0]
set Argu2 [lindex $argv 1]
if {$argc == 2} {
if {[regexp {^(\d|[1-9]\d|1\d\d|2[0-4]\d|[2][5][0-5])\.(\d|[1-9]\d|1\d\d|2[
0-4]\d|[2][5][0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|[2][5][0-5])\.(\d|[1-9]
\d|1\d\d|2[0-4]\d|[2][5][0-5])$} $Argu1 match ]} {
puts "VALID IP-ADDRESS"
set timeout $Argu2-1
spawn ping $Argu1
expect "Expect"
set string $expect_out(buffer)
puts $string
puts "SUCCESS"
exit
} else {
puts "INVALID IP-ADDRESS"
}
} else {
puts "YOU HAVE TO GIVE TWO ARGUMENTS\n FIRST ARGUMENT SHOULD BE
IP-ADDRESS \n SECOND ARGUMENT SHOULD BE THE NUMBER OF PACKETS
YOU WANT TO SEND"
}

Answer 1

I'm reluctant to answer your question, as you haven't responded to my answer on another question. However, seeing as nobody else has responded, I'll try to help you out.
I don't think you need to use $expect_out(buffer) here. Assuming that a ping returning "0% loss" or "0% packet loss" means the ping was successful, you could try the following (untested). Obviously, you can change the "0%" to whatever you want to signify success.
#!/usr/bin/expect
package require Expect
set Argu1 [lindex $argv 0]
set Argu2 [lindex $argv 1]
if {$argc == 2} {
if {[regexp {^(\d|[1-9]\d|1\d\d|2[0-4]\d|[2][5][0-5])\.(\d|[1-9]\d|1\d\d|2[
0-4]\d|[2][5][0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|[2][5][0-5])\.(\d|[1-9]
\d|1\d\d|2[0-4]\d|[2][5][0-5])$} $Argu1 match ]} {
puts "VALID IP-ADDRESS"
set timeout $Argu2-1
spawn ping $Argu1
expect {
"0%" {puts "The IP address was successfully pinged"}
"default" {puts "Could not ping this IP address"}
}
exit
} else {
puts "INVALID IP-ADDRESS"
}
} else {
puts "YOU HAVE TO GIVE TWO ARGUMENTS\n FIRST ARGUMENT SHOULD BE
IP-ADDRESS \n SECOND ARGUMENT SHOULD BE THE NUMBER OF PACKETS
YOU WANT TO SEND"
}
The reason I suggest "0%" is as follows. If you do a successful ping from a Windows machine you will see something like this (note the "0% loss"):
C:\Documents and Settings\Brian>ping 192.168.1.1
Pinging 192.168.1.1 with 32 bytes of data:
Reply from 192.168.1.1: bytes=32 time=1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Ping statistics for 192.168.1.1:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 1ms, Average = 0ms
From a Unix machine, it might look like this (note the "0% packet loss") :
[brian#rex 4]$ ping -c 1 192.168.1.87
PING 192.168.1.87 (192.168.1.87) 56(84) bytes of data.
64 bytes from 192.168.1.87: icmp_seq=0 ttl=64 time=42.1 ms
--- 192.168.1.87 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 42.153/42.153/42.153/0.000 ms, pipe 2
You could pick many indicators of a successful ping, I chose the fact that there was a 0% loss of packets (a clear indicator of success). The expect command searches the result of the ping and if it finds "0%", it outputs "The IP address was successfully pinged".