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       comedi_do_insnlist - perform multiple instructions


       #include <comedilib.h>

       int comedi_do_insnlist (comedi_t * device, comedi_insnlist * list);


       The function comedi_do_insnlist() performs multiple Comedi instructions
       as part of one system call.  In addition, Comedi  attempts  to  perform
       the  instructions  atomically,  that  is, on standard Linux kernels, no
       process preemption should occur during the instructions.  However,  the
       process may be preempted before or after the group of instructions.

       This  function  can  be  used  to avoid the overhead of multiple system
       calls,  or  to  ensure  that  multiple   instructions   occur   without
       significant delay between them.

       Preemption  may  occur if any of the instructions or the data arrays of
       any of the instructions exist in non-resident or copy-on-write pages.


       The function comedi_do_insnlist() returns  the  number  of  sucessfully
       completed   instructions.    Error   information  for  the  unsucessful
       instruction is not available.  If there is an error  before  the  first
       instruction can be executed, -1 is returned.

                                28 October 2007