a number of libraries, such as libgphoto and libptp, used by applications such as digiKam and F-Spot. As on Microsoft Windows there is no native support on Linux, but by means of GVfs the devices can easily be mounted and made available to applications that use standard POSIX commands and library functions. Android has PTP support, although as with MTP, a limitation is that when transferring photos from one's computer to the Android device, file timestamps are replaced with the time of the copy (with copies in the other direction, from device to computer, timestamps are preserved). The Poseidon USB stack on Amiga includes ptp.class. Version 1.1 PTP v1.1 (ISO 15740:2008) is an update to PTP published by ISO. This updated version of PTP is fully backward-compatible with PTP v1.0, and offers optional performance, compatibility, and feature enhancements including: A mechanism for handling streaming content A mechanism to support multiple vendor extension sets Support for objects larger than the 4GiB size limit set by PTP v1.0, by requiring 64 bits (8 bytes) for object size Support for retrieval of ObjectHandles in enumerated chunks. This may reduce long response times for some devices that possess large numbers of objects Support for arbitrary resizing prior to image transmission (responder scaling). In PTP v1.0, image sizes might be requested in full-resolution or thumbnail size only Support for arrays of datasets. This can be used to reduce the number of required transactions necessary for device characterization from being a function of the number of objects on the device down to one A fast file characterization operation that exploits dataset arrays to request, in a single transaction, only the minimum data required to characterize a typical filesystem A new standard ObjectFormatCode to support the Digital Negative (DNG) file format Drawbacks Renaming file objects directly is not possible without copying or rewriting them Modification of file contents is not supported (the file needs to be re-transferred completely) Some drawbacks are OS-specific — see See also Design rule for Camera File system PictBridge References External links PTP transport over USB specifications, USB.org. Microsoft and FotoNation Team to Support the Media Transfer Protocol For Wireless Digital Still Cameras, Microsoft News Center. Free software with PTP support Digital photography Network protocols ISO standards Computer-related introductions in 2000