Grep and print a pattern and also print a preceding string/pattern

Question

I need to grep for a ip address, and then find a specific line that precedes the ip address and print that line only

I ran the netsh and store in SSID.txt

SSID.txt

SSID1:TESTWIFI_1
BSSID1:1.1.1.1

SSID2:TESTWIFI_2
BSSID1:2.2.2.2
BSSID2:3.3.3.3
BSSID3:4.4.4.4

I want to grep 4.4.4.4

grep '4.4.4.4' SSID.txt | cut -d: -f2-

And then find the first instance of SSID before the ip address.

I know how to print a specific number of lines after using grep but I don't want to do that because there are an inconsistent amount of BSSIDS under each SSID

grep -A[] or -B [num] 

Desired Output

4.4.4.4 - SSID2:TESTWIFI_2

Answer 1

Could you please try following, this should be an easy task for awk program.

awk 'BEGIN{FS=":";OFS=" - "} /^SSID[0-9]/{val=$0;next} /4\.4\.4\.4/ && val{print $2,val}' Input_file

Adding a non-one liner form of above code now:

awk '
BEGIN{
  FS=":"
  OFS=" - "
}
/^SSID[0-9]/{
  val=$0
  next
}
/4\.4\.4\.4/ && val{
  print $2,val
}
'  Input_file

Explanation: Adding explanation of above code.

awk '                       ##Starting awk program here.
BEGIN{                      ##Starting BEGIN section here for program.
  FS=":"                    ##Setting FS field separator as : colon here.
  OFS=" - "                 ##Setting output field separator as space - space for all lines.
}                           ##Closing BEGIN section of this program here.
/^SSID[0-9]/{               ##Checking condition if any line starts from SSIDand digit then do following.
  val=$0                    ##Creating variable val whose value is current line value.
  next                      ##next will skip all further statements from here.
}
/4\.4\.4\.4/ && val{        ##Checking condition if a line has 4.4.4.4 escaping DOT here to take it as literal character and checking condition if val is NOT NULL.
  print $2,val              ##Printing $2 of current line and variable val here.
}
'  Input_file               ##Mentioning Input_file name here.

Answer 2

Another approach:-

awk -v S="4.4.4.4" '/^SSID/{v=$0;next}$0~S{print S " - " v}' SSID.txt