NZBGet is a two-part program, both perl scripts.

NVBGet-cache fetches file segments specified in a NZB file from a NNTP server. It isn't the fastest downloader (It's fetch-wait-fetch-wait cycle is very inefficient), but it does have one use: Retrieving hard-to-get files. If the first server specified cannot get all the segments, it will cache all those it can. Another server may then be specified, and NZBGet-cache will attempt to retrieve only those segments it doesn't already have. This may be repeated until enough data is recovered to use par2, or all available servers have been exausted.

NZBGet-extract doesn't fetch any files from a server. It just takes the cached segments downloaded from NZBGet-cache and assembles them into a .ntx file, which can then be decoded with yydecode to give you the files you want.

NZBGet-cache creates a set of folders when first run, called 0 through f. These are the cache where segments get stored. NZBGet-extract creates a folder called out, where it will place the .ntx file.
