vlbufferreset(3dm)

NAME
     vlBufferReset, vlBufferDone, vlBufferGetFd, vlBufferAdvise, vlNodeGetFd,
     vlDMBufferResetNode - VL buffer state management routines

SYNOPSIS
     #include <dmedia/vl.h>

     int vlBufferReset(VLServer svr, VLBuffer buffer);
     int vlBufferDone(VLBuffer buffer);
     int vlBufferGetFd(VLBuffer buffer);
     int vlBufferAdvise(VLBuffer buffer, int advice);
     int vlNodeGetFd(VLServer vlServer, VLPath path, VLNode node);
     int vlDMBufferResetNode(VLServer vlServer, VLPath path, VLNode node);

PARAMETERS
     svr        Specifies the server handle.

     path     Specifies the path handle.

     node     Specifies the node handle.

     buffer   Specifies the buffer handle.

     advice   Specifies the advice for the buffer.

DESCRIPTION
     vlBufferReset will reset the buffer so that the done flag is not set, and
     the buffer can have data written into it again.

     vlBufferDone returns the value of the buffer done flag. If this flag is
     positive, the buffer cannot have any valid data written into it. In this
     case vlGetNextFree(3dm) will always fail.

     vlBufferGetFd returns a file descriptor that can be used with select(2)
     to determine if there are frames available to be read (the file
     descriptor is readable) or written (the file descriptor is writable).
     This file descriptor will be invalid when the buffer is destroyed with
     vlDestroyBuffer.

     vlNodeGetFd returns a file descriptor that can be used with select(2) to
     determine if there is video data available to be read.

     vlDMBufferResetNode can be called after vlEndTransfer to clear the
     specified memory node of any outstanding DMBuffers sent to the specified
     node.

     Both vlNodeGetFd and vlDMBufferResetNode can only be used after a
     DMbufferPool has been registered to a path and node using
     vlDMPoolRegister(3dm). Video data must be read using
     vlDMBufferGetValid(3dm).
     vlBufferAdvise tells the library information about how the buffer will be
     used.  VL_BUFFER_ADVISE_NOACCESS VL_BUFFER_ADVISE_ACCESS

RETURN VALUE
     Upon successful completion, vlBufferReset will return VLSuccess,
     otherwise -1 is returned.  vlBufferDone will return >= 0 value on
     success, and -1 otherwise.  vlBufferGetFd will return >= 0 value on
     success, and -1 otherwise.

CAVEATS
     vlNodeGetFd and vlDMBufferResetNode return -1 with vlErrno set to
     VLAPIConflict on the O2 platform.  See vlintro(3dm) for a complete
     listing of compatible and incompatible routines.

SEE ALSO
     vlCreateBuffer(3dm), vlGetNextFree(3dm), vlDMPoolRegister(3dm),
     vlDMBufferGetValid(3dm), vlintro(3dm)