Use parentheses to capture the match; this will save it into $1: 
while (<>) {
        s/((?<!\\)\$[a-zA-Z0-9_]+)/change_name($1)/eg;
}

[download]
update: Hmmm... it seems the old guy beat me to it ;-)

[ ar0n ]

In reply to (ar0n) Re: substition problem by ar0n
in thread substition problem by cghost23

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