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>comedi_mark_buffer_read</H1
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>Name</H2
>comedi_mark_buffer_read -- streaming buffer control</DIV
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>Synopsis</H2
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>#include <comedilib.h></PRE
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><CODE
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>int comedi_mark_buffer_read</CODE
>(comedi_t * device, unsigned int subdevice, unsigned int num_bytes);</CODE
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> Description
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>The function comedi_mark_buffer_read() is used on a subdevice
that has a Comedi input command in progress. It should only be used
if you are using a mmap() (as opposed
to calling read() on the device file) to read data from Comedi's buffer,
since Comedi will automatically keep track of how many bytes have been
transferred via read() calls. This function is
used to indicate that the next num_bytes bytes in the buffer
are no longer needed and may be discarded.
If there is an error, -1 is returned.</P
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