grep IP addresses in expect script

Question

This is part of code in an expect script, I have a problem with searching IP addresses from a file whose name is in the variable $filename.

#!/usr/local/bin/expect -- 
###Made by Etihkru####


set env(TERM) vt100
set env(SHELL) /bin/sh
set env(HOME) /usr/local/bin
exp_internal 1
set PASSWORD eri
set SIU [lindex $argv 0]
match_max 1000
if {$SIU == ""} {
puts "Missing name of SIU. Run command as perl SIUADD FRTXXX"
exit
}


spawn ssh mashost
set USER admin
set PASS hidden

expect {
    "assword"  {send "$PASSWORD\r"}
}

        expect "ranosusr@rn2osscs603"
        send -- "cd /var/opt/ericsson/edd/ARNE_SIU \r"
        expect "ranosusr@rn2osscs603"
        send -- "grep -il $SIU *\r"
        set prompt {ranosusr@rn2osscs603> }
        expect -re "(FXL\\S+\\.xml).*$prompt$"
        set filename $expect_out(1,string) 
        send -- "cat $filename | grep 'url=' \r"
        expect -re "something.*$prompt$" //Expect this ip adreess ???
        set IP $expect_out(1,string)//put it to variable IP ???


spawn ssh admin@$ip
expect {
    -re "RSA key fingerprint" {send "yes\r"}
    timeout {puts "Host is known"}
}

expect {
    "assword"  {send "$PASS\r"}
}

expect "Osmon>"
send -- "resumePMMeasurements STN=0,MeasurementDefinition=0 sftp://pmup-rn2sossv605:eric@10.211.149.60/GRAN/rn2sossv605/$SIU/NeTransientUp \r"
expect "Osmon>"
send -- "getalarmlist \r"
expect -re "(\Operation Succeed\)"
send -- "rev \r"
expect "Osmon>"
send -- "subscribe 10.211.149.40 1 \r"
expect "Osmon>"
send -- "getsubscriptionstatus 1 \r"
expect "Osmon>"
interact

This is the ouput:

 expect: does "> cat FXL704_FRTAMX_SIU_ARNE.xml | grep 'url=' " (spawn_id exp4) match glob pattern "ranosusr@rn2osscs603"? no
    expect: does "> cat FXL704_FRTAMX_SIU_ARNE.xml | grep 'url=' \r\r\n" (spawn_id exp4) match glob pattern "ranosusr@rn2osscs603"? no
                          <emUrl url="10.80.31.123"/>    
    expect: does "> cat FXL704_FRTAMX_SIU_ARNE.xml | grep 'url=' \r\r\n                  <emUrl url="10.80.31.123"/>\r\r\n" (spawn_id exp4) match glob pattern "ranosusr@rn2osscs603"? no
    ranosusr@rn2osscs603>
    expect: does "> cat FXL704_FRTAMX_SIU_ARNE.xml | grep 'url=' \r\r\n                  <emUrl url="10.80.31.123"/>\r\r\nranosusr@rn2osscs603> " (spawn_id exp4) match glob pattern "ranosusr@rn2osscs603"? yes

I need the pure IP address, cleared from other characters (e.g. 10.80.31.123), because I need to use it in next SSH login, so I need to assign it to a variable $IP.

Answer 1

Your main problem is this line

cat $filename | grep {1,3\}\.\{1,3\}\.\{1,3\}\.\{1,3\} \r"

Apart from the useless use of cat, the main mistake is that {1,3} means "match 1,2 or 3" times, but your not telling it what to match. The syntax is also wrong, {} need to be escaped for regular grep. What you are looking is better written as:

grep -Po '\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}' filename

This uses PCRE syntax (-P) where \d means "digits" and which I find easier but to use standard grep regular expressions (BREs) you could do:

grep -o '[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}'

• The -o makes grep print only the matching part of the line.

• You never want to match the end of line character, there's no need. You should always try and make your regular expressions as simple as possible. It is always best to use the smallest, simplest expression that matches your data.

• You most certainly don't want to search for \r. While Windows does end lines with \r\n, most systems don't and in any case, there's little point in looking for it. If you need to match to the end of a line, use $ which will work in all cases.

Anyway, to save in a variable do this:

ip=$(grep -Po '\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}' filename)

You can now echo $ip to print the IP.

---

Based on your last edit, I am assuming that you want the ip defined by the ipAddress tag. I will now give you the obligatory warning: NEVER use regular expressions to parse XML or similar formats. That said, to get only the ipAddress IP, do this:

ip=$(grep -Po 'ip_v4="\K[0-9.]+' $filename)

The \K discards whatever was matched before it so you get only the IP part and since you know that the IP you are looking for is always preceded by ip_v4=", you can simply look for the longest string that contains only numbers and ..