1cfaef9617
Change SNDRV_PCM_VERSION, SNDRV_RAWMIDI_VERSION and SNDRV_TIMER_VERSION to indicate the addition of the time64 version of the mmap interface and these ioctl commands: SNDRV_PCM_IOCTL_SYNC SNDRV_RAWMIDI_IOCTL_STATUS SNDRV_PCM_IOCTL_STATUS SNDRV_PCM_IOCTL_STATUS_EXT SNDRV_TIMER_IOCTL_TREAD SNDRV_TIMER_IOCTL_STATUS 32-bit applications built with 64-bit time_t require both the headers and the running kernel to support at least the new API version. When built with earlier kernel headers, some of these may not work correctly, so applications are encouraged to fail compilation like #if SNDRV_PCM_VERSION < SNDRV_PROTOCOL_VERSION(2, 0, 15) extern int __fail_build_for_time_64[sizeof(long) - sizeof(time_t)]; #endif or provide their own updated copy of the header file. At runtime, the interface is unchanged for 32-bit time_t, but new kernels are required to work with user compiled with 64-bit time_t. A runtime check can be used to detect old kernel versions and warn about those. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.