adjust_mask() - read mask adjustments from file.

INTERFACE:

    subroutine adjust_mask(fn)
    IMPLICIT NONE

DESCRIPTION:

Read mask adjustments from file. The file format allows comments. Comment characters are ! or # - they MUST be in column 1. Lines with white-spaces are skipped. Conversion errors are caught and an error condition occurs. INPUT PARAMETERS:

    character(len=*), intent(in)        :: fn

REVISION HISTORY:

LOCAL VARIABLES:

    integer                   :: unit = 25 ! kbk
    character(len=255)        :: line
    integer                   :: iostat
    integer                   :: i,j,k=0,n=-1
    integer                   :: il,jl,ih,jh