I'm using aria2 to download a list of files that is dynamically generated. I want it to skip the files that are already in the download directory, but instead of doing this, it just re-downloads them and adds a .1 to the filename. I tried using --check-integrity=true, but that did not change the behavior. Is there a way to make it skip files that already exist?
Try adding --continue=true to your command.
According to the aria2c(1) man-page, -c, --continue[=true|false]:
Continue downloading a partially downloaded file. Use this option to resume a download started by a web browser or another program which downloads files sequentially from the beginning. Currently this option is only applicable to HTTP(S)/FTP downloads.