grep to IP address when IP address in parameter

Question

I need to grep to IP address ( as the following example ) , I use ksh script ,

    #  ifconfig -a |  /usr/xpg4/bin/grep   "100\.106\.2\.120 "
    inet 100.106.2.120 netmask ffffff00 broadcast 100.106.2.255

but how to grep IP address from parameter ( IP_ADDRESS ) ?

how to add the back slash in this case

IP_ADDRESS=192.2.34.2 , or IP_ADDRESS=192.2.34.20 ... etc

    #  ifconfig -a |  /usr/xpg4/bin/grep   "$IP_ADDRESS "

Thor · Accepted Answer · 2013-02-07T17:21:40.633

3

If you are using the bash shell you can Use parameter expansion:

ifconfig -a | /usr/xpg4/bin/grep "${IP_ADDRESS//./\\.}"

If your shell doesn't support this type of parameter expansion, you could use shell expansion instead, e.g. with sed:

ifconfig -a | /usr/xpg4/bin/grep `echo $IP_ADDRESS | sed 's/\./\\./g'`

or perl:

ifconfig -a | /usr/xpg4/bin/grep `echo $IP_ADDRESS | perl -pne 's/\./\\./g'`

edited Feb 07 '13 at 17:21

answered Feb 07 '13 at 11:41

Thor

I use the ksh shell not the bash shell – yael Feb 07 '13 at 11:43
@yael: many versions of ksh also support this type of parameter expansion. – Thor Feb 07 '13 at 11:46
my ksh not support it - # ifconfig -a | /usr/xpg4/bin/grep "${IP_ADDRESS//./\\.}" ksh: "${IP_ADDRESS//./\\.}": bad substitution – yael Feb 07 '13 at 11:47
@yael: alternatively you could use shell expansion, see edit. – Thor Feb 07 '13 at 17:22

1 Answers1