




The function clear-external-image-conversions clears the external image conversions for a port. If 
gp-or-null
 is nil all conversions are cleared using the image-color-users. If 
all
 is non-nil all conversions for all ports are cleared using 
gp-or-null
. Conversions are also freed if 
free-image
 is non-nil. By default, 
free-image
 is t, 
all
 is (null 
gp-or-null
), and 
errorp
 is t.
CAPI User Guide and Reference Manual (Windows version) - 3 Aug 2017