使用 UF_MODL_ask_extrusion问题

pppflak

我用以下代码去得到一个拉伸特征的信息.但是执行之后却什么都得不到.运行错误代码为"UNKNOWN FEATURE TYPE".请问我程序哪里出错了啊??我做测试的模型是一个在ug手动拉伸的正方形.希望各位高手指点啊....
1 W8 b; |) |1 `3 ctag_t part1;
5 g/ }& H$ B' u2 z: Z5 P% x: eint type=UF_feature_type;
tag_t feature=NULL_TAG;
int a;
" ?$ s: \* T( {* j0 U  u! c6 ~  Xchar * feature_type;
char msg[100];
int * n_o;
; e5 ^7 b. r0 ~! gtag_t * objects;
* q7 K# O# a: |0 \UF_MODL_SWEEP_TRIM_object_p_t trim_ptr;
& w3 n: o' s' m$ Fchar * taper_angle;
0 U$ m' S2 F) g- ~9 uchar *limits[2];
9 o' y+ u9 M" ?. C& lchar *offsets[2];
double region_point[3],direction[3];
, S1 `* T2 g7 `0 \9 Klogical * region_specified;
4 @9 J' ]) T7 E. Y1 y" i$ r- x% Xlogical * solid_creation;
' Y, u, z7 Q$ p1 y3 \* Dpart1=UF_PART_ask_nth_part(0);
- B: p0 N1 a( P- d# HUF_OBJ_cycle_objs_in_part(part1,type,&feature);
for (i=0;feature!=NULL;i++)
{
1 f% B9 x5 x8 j    UF_OBJ_cycle_objs_in_part(part1,type,&feature);
    UF_MODL_ask_feat_type(feature,&feature_type);
* @. P, M1 F8 E   if(strcmp(feature_type,"EXTRUDE")==0)
   {
    a=UF_MODL_ask_extrusion(feature,n_o,&objects,&trim_ptr,&taper_angle,limits,offsets,region_point,region_specified, solid_creation,direction );
4 k: d1 }0 L: `3 q) `4 f    UF_get_fail_message(a,msg);
    uc1601(msg,1);
. y! k( {! c: y! b* A# u* E$ ^8 B   }
}