Question

Looking for some ideas on how to accomplish this.

Every week I get a zip of about 10-15 text files, always with the same filenames. The files contain comma separated values. (the overall size of all the files, under 20mb).

I need to compare the contents of each text file in the zip on a weekly basis. If there is no difference basically do nothing, if there is a change replace the older files with the new ones, and also output the changes to a text file.

Answer 1

Compare their md5’s

if (md5_file('old.file') != md5_file('new.file')) {
    // the files are different, replace
}

And changes can be retrieved with console diff

$changes = `diff new.file old.file`;