The easiest way IMO is to use the -i command like switch, provided this is all the script has to do, either on the command line 
    perl -i.bak file

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script: 
    while(<>) {
        s/oldline/newline/g;
        print;
    }

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or including the -p switch: 
    s/oldline/newline

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where both the while loop and the print are implicit.

Or, alternatively, do it in the shebang line: 

    #! perl -i.bak -p
    s/oldline/newline/

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In reply to Re: changing data by bart
in thread changing data by DS

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