.\"Copyright 2010 (c) EPFL .TH EGD_START 3 2010 "EPFL" "EEGDEV library manual" .SH NAME egd_start, egd_stop - start and stop buffered acquisition .SH SYNOPSIS .LP .B #include .sp .BI "int egd_start(struct eegdev* " dev ");" .br .BI "int egd_stop(struct eegdev* " dev ");" .br .SH DESCRIPTION .LP \fBegd_start\fP() marks the beginning of buffered acquisition from the device referenced by \fIdev\fP. This means that the data starts getting accumulated in an internal ringbuffer and this buffered data can be sequentially obtained by successive calls to \fBegd_get_data\fP(3). A buffered acquisition started implies that the user has to get the data often enough to prevent the situation of a full ringbuffer. .LP \fBegd_stop\fP() halts the buffered acquisition of the device referenced by \fIdev\fP, relieving the user from the obligation to get data regularly. .SH "RETURN VALUE" .LP The function returns 0 in case of succes. Otherwise, \-1 is returned and \fIerrno\fP is set accordingly. .SH ERRORS .LP \fBegd_start\fP() and \fBegd_stop\fP() will fail if: .TP .B EINVAL \fIdev\fP is NULL. .SH "SEE ALSO" .BR egd_get_data (3), .BR egd_get_available (3)