PROGRAM commandline
IMPLICIT NONE
REAL :: num
INTEGER :: option2, N
CHARACTER(LEN=100) :: arg, option1

!Example to read a character and an integer from the command line.
!For example try,
! >> ./a.exe inputfilename 21

!Read input from the command line
N = IARGC()
IF (N < 1) THEN
 write(*,'(a)') "usage:  ./foo option1 option2"
 write(*,'(a)') "        option1=character"
 write(*,'(a)') "        option2=integer"
ELSE
 CALL GETARG(1,option1)     !Grab the first command line argument
                            ! and store it in the variable 'option1'

 CALL GETARG(2,arg)         !Grab the 2nd command line argument
                            ! and store it in the temporary variable
                            ! 'arg'
 read(arg,*) option2        !Now convert string to integer

write(*,*) "Variable option1 = ", trim(adjustl(option1))
write(*,*) "Variable option2 = ", option2
ENDIF


END PROGRAM commandline