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Content of torrent file


I have a question about the torrent file. I know that it contains a list of servers (users) that I need to connect to, for downloading part of the whole file.

my question is if this is all what the torrent contains? there are more important details?

thanks!


Solution

  • A torrent file is a specially formatted binary file. It always contains a list of files and integrity metadata about all the pieces, and optionally contains a list of trackers.

    A torrent file is a bencoded dictionary with the following keys:

    announce - the URL of the tracker
    info - this maps to a dictionary whose keys are dependent on whether one or more files are being shared:
        name - suggested file/directory name where the file(s) is/are to be saved
        piece length - number of bytes per piece. This is commonly 28KiB = 256 KiB = 262,144 B.
        pieces - a hash list. That is, a concatenation of each piece's SHA-1 hash. As SHA-1 returns a 160-bit hash, pieces will be a string whose length is a multiple of 160-bits.
        length - size of the file in bytes (only when one file is being shared)
        files - a list of dictionaries each corresponding to a file (only when multiple files are being shared). Each dictionary has the following keys:
            path - a list of strings corresponding to subdirectory names, the last of which is the actual file name
            length - size of the file in bytes.