(PECL rrd >= 0.9.0)
rrd_first — Gets the timestamp of the first sample from rrd file
Returns the first data sample from the specified RRA of the RRD file.
file
RRD database file name.
raaindex
The index number of the RRA that is to be examined. Default value is 0.
Integer number of unix timestamp, o false
in caso di fallimento.