Given an ip_value, find the address of the unwind information
block operating system-specific data area, if present, and
write it to unwind_ossd_p. If not present, then write 0 to
unwind_ossd_p.
Format
LIB$X86_GET_UNWIND_OSSD (ip_value, unwind_ossd_p)
Additional Information:
explode
extract