




The function printer-port-supports-p detects if the printer port can support the feature named by 
feature
.
If port is passed it should be the value bound to var in with-print-job. If port is not supplied it defaults to the current printer port (dynamically bound within with-print-job).
supportedp indicates if the feature is supported.
validp indicates if the feature was recognized.
Currently the only value of 
feature
 that is recognized is :postscript and the 
supportedp
 value is true if the printer supports PostScript.
CAPI User Guide and Reference Manual (Unix version) - 25 Feb 2015