Need Sed or any script to remove whitespace between characters and replace with underscores

I have an large language .ini file whose lines look like this:

CC MY APPS=My aplications
CC MY APPLICATION SETTINGS TITLE=My Settings

I need to remove all whitespace开发者_StackOverflows between CC and = and replace with underscores like this:

CC_MY_APPS=My aplications
CC_APPLICATION_SETTINGS_TITLE=My Settings

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It is better to use awk

$ awk 'BEGIN{OFS=FS="="}{gsub(/ /,"_",$1)}1' file
CC_MY_APPS=My aplications
CC_MY_APPLICATION_SETTINGS_TITLE=My Settings

Alternatively if you have Ruby(1.9+)

$ ruby -F"=" -ane '$F[0].gsub!(/\s+/,"_");puts $F.join("=")' file

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A perl way to do it, very similar to kurumi's solution in Ruby :

perl -i.orig -F= -ane '$F[0]=~s/\s+/_/g;print join"=",@F' file.ini

The original file will be saved into file.ini.orig

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Alternatively, if your values don't contain a '=', you could try:

perl -pi.bak -e 's/\s+(?=.*=)/_/g' file.ini

using a look-ahead.