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search pattern if found do not add if not found add

Hi Colucix,

I am trying to get a result out of this but fails please help. Have two files /tmp/1 & /tmp/hosts.

/tmp/1
IP=123.456.789.01
WAS_HOSTNAME=abcdefgh.was.tb.dsdc

/tmp/hosts
123.456.789.01

I want this result in /tmp/hosts if hostname is already there dont want duplicate entry.

This is wrong
123.456.789.01 abcdefgh.was.tb.dsdc abcdefgh.was.tb.dsdc

This is correct
123.456.789.01 abcdefgh.was.tb.dsdc

Trying with this:

if grep abcdefgh.was.tb.dsdc /tmp/hosts; then
. /tmp/1 && sed -i "s/^$IP$.*$$/$IP\1 $WAS_HOSTNAME/" /tmp/hosts;
fi

Thanks in advance

The if grep abcdefgh.was.tb.dsdc /tmp/hosts part checks if the string is present, you need to know if the string is not present.

Try this:

Code:

if ! grep abcdefgh.was.tb.dsdc /tmp/hosts 

then

  . /tmp/1 && sed -i "s/^$IP$/$IP $WAS_HOSTNAME/" /tmp/hosts

fi

I also changed your sed statement, yours seems to elaborate.