Usage with 'http' (HTTPie):
    http -f http://api.x3dna.org/dssr [options] url=|model@
    http http://api.x3dna.org/dssr/help   -- display this help message

Options:
    json=true-or-FALSE(default)    [e.g., json=true # JSON output]
    pair=true-or-FALSE(default)    [e.g., pair=1    # base-pair only]
    hbond=true-or-FALSE(default)   [e.g., hbond=t   # H-bonding info]
    more=true-or-FALSE(default)    [e.g., more=y    # further details]

Required parameter:
    url=URL-to-coordinate-file [e.g., url=https://files.rcsb.org/download/1ehz.pdb.gz]
    model@coordinate-file      [e.g., model@1ehz.cif]
    # Only one must be specified. 'url' precedes 'model' when both are specified.
    # The coordinate file must be in PDB or PDBx/mmCIF format, optionally gzipped.

Examples:
    http -f http://api.x3dna.org/dssr url=https://files.rcsb.org/download/1ehz.pdb.gz
    http -f http://api.x3dna.org/dssr model@1ehz.cif pair=1
    # with 'curl'
    curl http://api.x3dna.org/dssr -F 'url=https://files.rcsb.org/download/1ehz.pdb.gz'
    curl http://api.x3dna.org/dssr -F 'model=@1msy.pdb' -F 'pair=1'

Note:
    The web API has an upper limit on coordinate file size (gzipped): < 6 MB