pub unsafe extern "C" fn spkcvt_c(
trgsta: *mut f64,
trgepc: f64,
trgctr: *mut u8,
trgref: *mut u8,
et: f64,
outref: *mut u8,
refloc: *mut u8,
abcorr: *mut u8,
obsrvr: *mut u8,
state: *mut f64,
lt: *mut f64,
)