| 
	    plP_checkdriverinit
	  ( | list ); | 
 Checks to see if any of the specified drivers have been
    initialized. Function tests a space-delimited list of driver names to
    see how many of the given drivers have been initialized, and how often.
    The return code of the function is: 0 if no matching
    drivers were found to have been initialized; -1 if
    an error occurred allocating the internal buffer; or, a positive number
    indicating the number of streams encountered that belong to drivers on
    the provided list. This function invokes plP_getinitdriverlist
    internally to get a complete list of drivers that have been initialized
    in order to compare with the driver names specified in the argument list
    to plP_checkdriverinit.
    
list
	  (char *, input)
	
	    Pointer to character string specifying a space-delimited
	    list of driver names, e.g., "bmp jpeg tiff".