[Question]Writing onto a file

Whenever I write onto a file it deletes what is before.

mailbody = fs.open(to, "w")
   mail = fs.open(to, "w")
   mail.writeLine("FromId: " .. id)
   mail.writeLine("FromName: " .. name)
   mail.writeLine("To: " .. to)
   mail.write(message..table.concat(mailbody,',\n'))
   mail.close()

Not really sure what you're trying to do there. Please give us the full code.

I think what you may be looking for is append mode, though.

Instead of using fs.open(file, "w"), use fs.open(file, "a")

This opens the file in append mode. Write mode clears the file first, but append mode appends to the end of the file.