Here’s a little terminal command I use to repeatedly attempt to download a file. This is useful if the transfer aborts frequently or if the server is busy:

As you can see I used this to download Parallels VM, because their servers keep dropping the connection after a while when they’re busy, which often happens when a new release comes out.

The while/do/done loop keeps calling curl, with pauses of 10 seconds. curl will keep returning a failure exit code, which is what keeps the while loop going if inverted with the ! (logical not) operator. The -C - flag tells curl to continue at the last byte position.