If "type" is UF_ATTR_reference then "value->value.string" must either be NULL or point to a character buffer of size UF_ATTR_MAX_STRING_LEN + 1. If the value is NULL, then the returned buffer will be allocated, and the user is responsible for freeing it by calling UF_free().什么意思
时间: 2024-02-10 08:34:12 浏览: 33
这段话是从Unigraphics NX API文档中摘录出来的。它描述了一个数据结构中的"type"字段为UF_ATTR_reference时,"value"字段的行为。如果"value->value.string"为NULL,则会分配一个缓冲区并返回给用户,用户需要使用UF_free()函数来释放它。另外,如果"value->value.string"指向一个字符缓冲区,则它的大小必须至少为UF_ATTR_MAX_STRING_LEN + 1。这个缓冲区将用于存储引用值。
相关问题
If "type" is UF_ATTR_reference then "value->value.string" must either be NULL or point to a character buffer of size UF_ATTR_MAX_STRING_LEN + 1. If the value is NULL, then the returned buffer will be allocated, and the user is responsible for freeing it by calling UF_free().
This looks like a code snippet from the Unigraphics NX API documentation. It describes the behavior of the "value" field of a data structure when the "type" field is set to UF_ATTR_reference. If "value->value.string" is NULL, then a buffer will be allocated and returned to the user, and the user is responsible for freeing it using the UF_free() function. Alternatively, if "value->value.string" points to a character buffer, it must be at least UF_ATTR_MAX_STRING_LEN + 1 in size. This buffer will be used to store the reference value.
if (memcmp(&vo_config->disp_rect, &def_disp_rect, sizeof(ot_rect)) != 0) { layer_attr->display_rect.width = vo_config->disp_rect.width; layer_attr->display_rect.height = vo_config->disp_rect.height; printf("CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC->display_rect.height = vo_config->disp_rect.height \n"); } layer_attr->img_size.width = layer_attr->display_rect.width; layer_attr->img_size.height = layer_attr->display_rect.height; /* set image size if changed. */ if (memcmp(&vo_config->image_size, &def_img_size, sizeof(ot_size)) != 0) { layer_attr->img_size.width = vo_config->image_size.width; layer_attr->img_size.height = vo_config->image_size.height; printf("CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC->img_size.height = vo_config->image_size.height \n"); }什么意思
这是一段 C 语言代码,主要作用是根据配置信息修改视频输出的参数。具体来说,代码中的 if 语句会比较当前配置信息中的显示区域(disp_rect)和默认显示区域(def_disp_rect),如果不相同则会将视频输出的显示区域宽度和高度设置为配置信息中的宽度和高度。同时,代码还会比较当前配置信息中的图像大小(image_size)和默认图像大小(def_img_size),如果不相同则会将视频输出的图像大小设置为配置信息中的宽度和高度。这些操作都是为了确保视频输出的参数能够符合用户的要求。其中的 printf 函数是用来输出一些调试信息的。