Lexmark C760 Technical Reference page 211

resolution
— resolution integer
queries the resolution for the current print job. An integer is returned on the
stack:
300
300 dpi is set to On
600
600 dpi is set to On
1200
1200 dpi is set to On
This operator is equivalent to executing the following PostScript emulation
sequence:
currentpagedevice /HWResolution get 0 get
Error: stackoverflow
revision
— revision integer
queries the Revision system parameter. An integer is returned on the stack to
indicate the revision level.
Error: stackoverflow
4-34
PostScript