~/nginx-0.6.31/src$ grep -R request_body_file_group_access *
http/ngx_http_request.h:    unsigned
request_body_file_group_access:1;
http/modules/ngx_http_dav_module.c:        r-
>request_body_file_group_access = 1;

http/ngx_http_request_body.c:            if (r-
>request_body_file_group_access) {

http/ngx_http_request_body.c:        if (r-

>request_body_file_group_access) {

http/ngx_http_request_body.c, ngx_int_t
ngx_http_read_client_request_body:

            if (r->request_body_file_group_access) {
                tf->access = 0660;
            }