program read_header

	parameter(max=40000)
	character nin*100
	real*4 x(max)

	nin='/home/sgao/demo/04_sac/st04.sac'
	call rsac1(nin, x, npts, beg, dt, max, nerr)
	call getfhv('EVLA', evlat, nerr)
	call getfhv('EVLO', evlon, nerr)
	call getfhv('EVDP', evdep, nerr)
	call getfhv('GCARC', gcarc, nerr)
	call getfhv('BAZ', baz, nerr)
	call getfhv('STLA', stlat, nerr)


* In the subroutine above, nin, x, and max are input, and
*	the rest are output.

	write(6,61) dt
61	format('The sampling interval is ', f6.3, ' seconds')
	print*,'The number of points in the file is ', npts
	print*,'The 10th data point is ', x(10)

	print*,'The event latitude is ', evlat
	print*,'The event longitude is ', evlon
	print*,'The event depth is ', evdep
	print*,'The epicentral distance in degree is ',gcarc 
	print*,'The back-azimuth is ', baz
	print*,'The station latitude is ', stlat


** Get the time of the first point in the file

	call getnhv('NZYEAR', nzyear, nerr)
	call getnhv('NZJDAY', nzjday, nerr)
	call getnhv('NZHOUR', nzhour, nerr)
	call getnhv('NZMIN', nzmin, nerr)
	call getnhv('NZSEC', nzsec, nerr)
	call getnhv('NZMSEC', nzmsec, nerr)

	print*,'The time of the first point in the SAC file is '
	print*,nzyear,':', nzjday,':',nzhour,
     &		':',nzmin,':',nzsec,':',nzmsec

	stop
	end

***********************************************
** To compile the program, copy and paste the
*following 3 lines into a file called Makefile and type make

*read_header.exe:read_header.f
*	gfortran -g -m64 read_header.f -o read_header.exe \
*/home/sgao/lib/sacio.a