Set the Floating Point Data registers with the values provided for the process associated with the file descriptor. You must have opened the file descriptor for writing. The argument is a pointer to a procfs_fpreg structure (see debug_fpreg_t in <sys/debug.h>) that specifies the values of the Floating Point Data registers. For example:

procfs_fpreg my_fpreg;

/* Set the members of my_fpreg as required. */
devctl( fd, DCMD_PROC_SETFPREG, my_fpreg, sizeof(procfs_fpreg),

To get the Floating Point Data registers, use DCMD_PROC_GETFPREG .