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    1 Open Sound System call redirector
    2 =================================
    3 
    4 The purpose of this little piece of code is to redirect
    5 OSS (Open Sound System) calls to any shared library to avoid
    6 overhead caused with the LD_PRELOAD wrapper. Especially, 
    7 wrapping select() and poll() functions cause big overhead.
    8 
    9 In ideal world, all OSS programs will use this little code
   10 to allow a sound emulation for OSS based APIs without requirement
   11 of ugly LD_PRELOAD hacks.
   12 
   13 Usage
   14 =====
   15 
   16 Set environment variable OSS_REDIRECTOR to name of dynamic library
   17 with lib_oss_* public functions. For example (ALSA):
   18 
   19 export OSS_REDIRECTOR=libalsatoss.so
   20 
   21 If this variable is not set, or this value is "oss" or "OSS",
   22 the direct system calls are used.
   23 
   24 Porting OSS application to use this code
   25 ========================================
   26 
   27 All functions have equivalent as using syscalls. Only one exception
   28 is select() or poll() usage. It is required to use oss_pcm_select*()
   29 or oss_pcm_poll*() wrappers to determine the "real" used file
   30 descriptors and mangle back the result.
   31 
   32 Note that the *prepare() functions returns the count of file
   33 descriptors allocated (poll) or the maximum used file descriptor
   34 (select).
   35 
   36 Porting example
   37 ===============
   38 
   39 FIXME: Add a link to a good patch.