You must restore an archive object before you read it. Do not call restoreObject for non-archive objects.

The status of an archived object throughout the restoration process is described as follows:
  1. By default, the archived object is in the frozen state.
  2. After you submit a restore request, the object is in the restoring state. It takes about one minute to complete the restore task.
  3. After the server completes the restore task, the object enters the restored state and you can read the object. By default, the restored state lasts 24 hours and can be extended by another 24 hours after you call RestoreObject again. During one restoration process, RestoreObject can be called on an object for up to seven times. In other words, an object can remain in the restored state for up to seven days.
  4. After the restored state expires, the object returns to the frozen state.

Run the following code to restore an object:

#include "oss_api.h"
#include "aos_http_io.h"
const char *endpoint = "<yourEndpoint>";
const char *access_key_id = "<yourAccessKeyId>";
const char *access_key_secret = "<yourAccessKeySecret>";
const char *bucket_name = "<yourBucketName>";
const char *object_name = "<yourObjectName>";
const char *object_content = "More than just cloud.";
void init_options(oss_request_options_t *options)
{
    options->config = oss_config_create(options->pool);
    /* Use a char* string to initialize aos_string_t. */
    aos_str_set(&options->config->endpoint, endpoint);
    aos_str_set(&options->config->access_key_id, access_key_id);
    aos_str_set(&options->config->access_key_secret, access_key_secret);
    /* Determine whether the CNAME is used. 0 indicates that the CNAME is not used. */
    options->config->is_cname = 0;
    /* Used to configure network parameters, such as timeout. */
    options->ctl = aos_http_controller_create(options->pool, 0);
}
int main(int argc, char *argv[])
{
    /* Call the aos_http_io_initialize method in main() to initialize global resources, such as networks and memories. */
    if (aos_http_io_initialize(NULL, 0) ! = AOSE_OK) {
        exit(1);
    }
    /* Memory pool used to manage memories, which is equivalent to apr_pool_t. The implementation code is included in the apr library. */
    aos_pool_t *pool;
    /* Re-create a new memory pool. The second parameter is NULL, indicating that it does not inherit from any other memory pools. */
    aos_pool_create(&pool, NULL);
    /* Create and initialize options. This parameter mainly includes global configuration information, such as endpoint, access_key_id, acces_key_secret, is_cname, and curl. */
    oss_request_options_t *oss_client_options;
    /* Allocate memories in the memory pool to options. */  
    oss_client_options = oss_request_options_create(pool);
    /* Use oss_client_options to initialize client options. */
    init_options(oss_client_options);
    /* Initialization parameters. */
    aos_string_t bucket;
    aos_string_t object;
    aos_list_t buffer;
    oss_acl_e oss_acl = OSS_ACL_PRIVATE;
    aos_buf_t *content = NULL;
    aos_table_t *headers = NULL;
    aos_table_t *resp_headers = NULL; 
    aos_status_t *resp_status = NULL; 
    aos_str_set(&bucket, bucket_name);
    aos_str_set(&object, object_name);
    headers = aos_table_make(pool, 0);
    /* Create a bucket of the archive storage class. */
    resp_status = oss_create_bucket_with_storage_class(oss_client_options, &bucket, oss_acl, OSS_STORAGE_CLASS_ARCHIVE, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("create bucket succeeded\n");
    } else {
        printf("create bucket failed\n");
    }
    aos_list_init(&buffer);
    content = aos_buf_pack(oss_client_options->pool, object_content, strlen(object_content));
    aos_list_add_tail(&content->node, &buffer);
    /* Upload a file. */
    resp_status = oss_put_object_from_buffer(oss_client_options, &bucket, &object, &buffer, headers, &resp_headers);
    if (aos_status_is_ok(resp_status)) {
        printf("put object from buffer succeeded\n");
    } else {
        printf("put object from buffer failed\n");      
    }    
    /* Restore the object. */
    do {
        headers = aos_table_make(pool, 0);
        resp_status = oss_restore_object(oss_client_options, &bucket, &object, headers, &resp_headers);
        printf("restore object resp_status->code: %d \n", resp_status->code);
        if (resp_status->code ! = 409) {
            break;
        } else {
            printf("restore object is already in progress, resp_status->code: %d \n", resp_status->code);
            apr_sleep(5000);
        }
    } while (1);
    /* Release the memory pool, that is, memories allocated to resources during the request. */
    aos_pool_destroy(pool);
    /* Release the allocated global resources. */
    aos_http_io_deinitialize();
    return 0;
}

For more information about the archive storage classes, see Introduction to storage classes. For more information about related status code, see RestoreObject.