Sensoray 811 Windows SDK - Manual (Page 13)

int devid
);
Sets the record mode (see mid811types.h for MID811_REC type definition).
Parameters
recMode
record mode.
devid
device id in the system (use 0 for first channel with a single board installed).
Returns
0 on success, negative value if error (see mid811types.h for error codes list).
MID811_API int S811_StartRecord(
char *fileName,
int devid
);
Starts recording to a file.
Parameters
fileName
full path to the target file, no extension.
devid
device id in the system (use 0 for first channel with a single board installed).
Returns
0 on success, negative value if error (see mid811types.h for error codes list).
MID811_API int S811_StartRecordW(
wchar_t *fileName,
int devid
);
Same as S811_StartRecord, but uses widechar or Unicode filenames.
MID811_API int S811_StopRecord(
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