I have CSV files upwards of 20 MB. I need to prepend a variable to the beginning of each line.

What would be the best way to do this?

I thought about opening up the file and and reading each line in one by one, prepending it, then writing it to a second file. Once the second file is finished the first one will be deleted.

Or I was thinking of loading it into memory all at once into a variable then doing a regex to to prepend that.

How would you guys recommend going about this?

In reply to Prepend Evey Line in a File by awohld

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