Help a newb with sed?

Shell Programming and Scripting
1

So here is my problem:

I need to do a sed search and replace on the following:

variable_blah_STATUS replaced with "replace string".

sed 's/variable_blah_STATUS/replace string/g' works great but there is a catch.

The catch is that I need to check and not replace variable_blah_STATUS if there is either a underscore before it or after it.

So:

_variable_blah_STATUS : do not replace
variable_blah_STATUS_ : do not replace
_variable_blah_STATUS_ : do not replace

variable_blah_STATUS : REPLACE!

Is there any easy way to do this with sed? I tried something with word boundaries using \b and it looked like it was just using it as part of the search string and it doesnt really help me with the whole underscore thing anyways. Obviously I think I need some regex stuff, but could not get it to work.

Thanks in advance for any help. It is greatly appreciated, this thing is driving me nuts.

2

It seems to me \b works fine?

sed 's/\bvariable_blah_STATUS\b/replace string/g

What did not work for you?

echo "variable_blah_STATUS _variable_blah_STATUS \
variable_blah_STATUS_ _variable_blah_STATUS_"\
|sed 's/\bvariable_blah_STATUS\b/replace string/g'

replace string _variable_blah_STATUS variable_blah_STATUS_ _variable_blah_STATUS_
3 
sed 's/\([^_]\)variable_blah_STATUS\([^_]\)/\1replace string\2/g' myFile

naaaah- not yet.......

4

Thanks so much for your help, however neither of those work for me. I am running on Sun Solaris if that makes any differance and my sed is from 2005 it says. Tried gsed as well to no avail. Any suggestions?

mcs -p /usr/bin/sed
/usr/bin/sed:
@(#)SunOS 5.10 Generic January 2005

echo "variable_blah_STATUS _variable_blah_STATUS \ variable_blah_STATUS_ _variable_blah_STATUS_" 
| sed 's/\([^_]\)variable_blah_STATUS\([^_]\)/\1replace string\2/g'
variable_blah_STATUS _variable_blah_STATUS
variable_blah_STATUS_ _variable_blah_STATUS_

echo "variable_blah_STATUS _variable_blah_STATUS \ variable_blah_STATUS_ _variable_blah_STATUS_" 
| sed 's/\bvariable_blah_STATUS\b/replace string/g'
variable_blah_STATUS _variable_blah_STATUS
variable_blah_STATUS_ _variable_blah_STATUS_