extracting values from configuration file

Shell Programming and Scripting
1

Dear All,

i am new to shell scripting, I am working on embedded system based on linux.I am supposed to the read the configuration file and edit another file.
presently I would like to read from the configuration file.It would be having values file one below.

There is chance of entering duplicate variable in configuration file however I need to extaract only the last entered value.

example file.conf

ChangeVersion=0
IPAddress=192.168.1.195
GATEIPAddress=192.168.1.1
WebServerIP=192.168.1.106
IPAddress=192.168.1.201
IPAddress=192.168.1.223

I need to extarct the change version,GATEIPAddress and IPAddress which comes as the last entry. How we can achive this.

Thanks in Advance,
Ratheendran

2

You could source the file. the duplicates will always have the last entry since it overwrites the previous entry.

. file.conf
or
source file.conf
3

See if this would work for you:

sed -n -e '/ChangeVersion/p' -e '/GATEIP/p' -e '$p' inp_file
4 
# cat tst
ChangeVersion=0
IPAddress=192.168.1.195
GATEIPAddress=192.168.1.1
WebServerIP=192.168.1.106
IPAddress=192.168.1.201
IPAddress=192.168.1.223

# nawk '/^IPAddress/{x=$0}/GATE/||/Version/{print}END{print x}' tst
ChangeVersion=0
GATEIPAddress=192.168.1.1
IPAddress=192.168.1.223

# nawk -F= '/ChangeVersion/||/IPAddress/{A[$1]=$2}END{for(i in A) print i"="A}' tst
GATEIPAddress=192.168.1.1
ChangeVersion=0
IPAddress=192.168.1.223

if it is sure that IPAddress is in last line then

# nawk '{x=$0}/GATE/||/Version/END{print x}' tst
ChangeVersion=0
GATEIPAddress=192.168.1.1
IPAddress=192.168.1.223
5

Thanks every one for your response.

I guess I need to make the requirements more clear.

I would like to get the values from config file and store them to a variable,since the chances of entering the duplicate fields are obvious.

 
#cat tst 
WebServerIP=192.168.1.106       
ChangeVersion=0                      
IPAddress=192.168.1.195              
GATEIPAddress=192.168.1.1            
GATEIPAddress=192.168.1.102            
WebServerIP=192.168.1.106            
IPAddress=192.168.1.201              
IPAddress=192.168.1.223              
HiSpeedNet=1                         
HiSpeedNet=2

so I need to retrieve last entered field and store it in a variable for subsequent manipulation.
e.g HiSpeedNet=2, IPAddress=192.168.1.223, GATEIPAddress=192.168.1.102 ..etc.

6

Could this help you ?

awk -F"=" '{b[$1]=$0;next} END{for(i in b) {print b}}' testfile
7

The first response is the answer you're looking for. See post #2 by anchal_khare.

Regards,
Alister