$ gemmi residues -h
Usage:
 gemmi residues [options] INPUT[...]
Prints one residue per line, with atom names.
  -h, --help          Print usage and exit.
  -V, --version       Print version and exit.
  --format=FORMAT     Input format (default: from the file extension).
  -mSEL, --match=SEL  Print residues/atoms matching the selection.
  -l, --label         Print 'label' chain ID and seq ID in brackets.
INPUT is a coordinate file (mmCIF, PDB, etc).
The selection SEL has MMDB syntax:
/mdl/chn/s1.i1(res)-s2.i2/at[el]:aloc (all fields are optional)