write mask {<xray-write-mask-statement>} end

<xray-write-mask-statement> :==

  ?
  --{Print information about current status.}
  from=<real-space-object>
  --{Source of mask to be written.}
  output=<filename>
  --{File for mask.}
  type=cns|omask
  --{Type of mask to write: cns or compressed O format. Default=omask}
  extent=molecule|unit|box|fractional-box|asymmetric-unit
  --{Mode for limits of omask. A cns mask is always written covering the 
     asymmetric unit. Default=molecule}
  cushion=<real>
  --{For extend=molecule mode the cushion around the molecule in Angstroms.
     Default=2.0A}
  xmin=<real> xmax=<real> ymin=<real> ymax=<real> zmin=<real> zmax=<real>
  --{For extend=box, limit of the mask in orthogonal Angstroms.
     For extend=fractional-box, limit of the mask in fractional coordinates.}