open (INFILE, "input.txt"); open (OUTFILE, ">output.txt"); while (INFILE) { $_ =~ s/foo/bar/gms; print OUTFILE "$_\n"; }

/m is multi line: not useful when dealing with a single line at a time. /s makes . match newline: not useful if you don't use ..

One liner: 

perl -i.backup -pe's/foo/bar/g' filename

[download]

Same thing, inside a larger script that you don't want to have using -i all the time: 

{
    local @ARGV = ('filename');
    local $^I = '.backup';
    local $_;
    while (<>) {
        s/y/yah/g;
        print;
    }
}

[download]

- Yes, I reinvent wheels.
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In reply to Re: reading/writing line by line by Juerd
in thread reading/writing line by line by amarceluk

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