pst_to_i          254 process.c      #define PST2INT(st) NUM2INT(pst_to_i(st))
pst_to_i          371 process.c          return rb_equal(pst_to_i(st1), st2);
pst_to_i         5067 process.c          rb_define_method(rb_cProcessStatus, "to_i", pst_to_i, 0);