1COMEDI_MARK_BUFFER_READ(3) COMEDI_MARK_BUFFER_READ(3)
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6 comedi_mark_buffer_read - streaming buffer control
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9 #include <comedilib.h>
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11 int comedi_mark_buffer_read (comedi_t * device, unsigned int subdevice,
12 unsigned int num_bytes);
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15 The function comedi_mark_buffer_read() is used on a subdevice that has
16 a Comedi input command in progress. It should only be used if you are
17 using a mmap() (as opposed to calling read() on the device file) to
18 read data from Comedi's buffer, since Comedi will automatically keep
19 track of how many bytes have been transferred via read() calls. This
20 function is used to indicate that the next num_bytes bytes in the buf‐
21 fer are no longer needed and may be discarded. If there is an error,
22 -1 is returned.
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24 28 October 2007 COMEDI_MARK_BUFFER_READ(3)