1COMEDI_MARK_BUFFER_WRITTEN(3) COMEDI_MARK_BUFFER_WRITTEN(3)
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6 comedi_mark_buffer_written - streaming buffer control
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9 #include <comedilib.h>
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11 int comedi_mark_buffer_written (comedi_t * device, unsigned int subde‐
12 vice, unsigned int num_bytes);
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15 The function comedi_mark_buffer_written() is used on a subdevice that
16 has a Comedi output command in progress. It should only be used if you
17 are using a mmap() (as opposed to calling write() on the device file)
18 to write data to Comedi's buffer, since Comedi will automatically keep
19 track of how many bytes have been transferred via write() calls. This
20 function is used to indicate that the next num_bytes bytes in the buf‐
21 fer are valid and may be sent to the device. If there is an error, -1
22 is returned.
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24 28 October 2007 COMEDI_MARK_BUFFER_WRITTEN(3)