
	opensf() exists only to provide backwards compatibility
	with some of the CARL software which relies on custom
	routines to read and write soundfiles.

	It takes one argument: the path and name of a soundfile.
	It returns a pointer to a "sndesc" structure, which contains
	an open file pointer to the soundfile.

	If an error occurs, NULL is returned, and the external variable
	"sferror" is set to a value defined in snd.h

	NOTE: use closesf(3CARL) to close the soundfile and free the
	sndesc structure.

	Abe Singer, June 1992
*/
