module namelist_utils 27,1
use string_utils
, only: to_lower
implicit none
private
! Public interface methods
public ::&
find_group_name ! find a specified namelist group in a file
!---------------------------------------------------------------------------------------
contains
!---------------------------------------------------------------------------------------
subroutine find_group_name(unit, group, status) 27,2
!---------------------------------------------------------------------------------------
! Purpose:
! Search a file that contains namelist input for the specified namelist group name.
! Leave the file positioned so that the current record is the first record of the
! input for the specified group.
!
! Method:
! Read the file line by line. Each line is searched for an '&' which may only
! be preceded by blanks, immediately followed by the group name which is case
! insensitive. If found then backspace the file so the current record is the
! one containing the group name and return success. Otherwise return -1.
!
! Author: B. Eaton, August 2007
!---------------------------------------------------------------------------------------
integer, intent(in) :: unit ! fortran unit attached to file
character(len=*), intent(in) :: group ! namelist group name
integer, intent(out) :: status ! 0 for success, -1 if group name not found
! Local variables
integer :: len_grp
integer :: ios ! io status
character(len=80) :: inrec ! first 80 characters of input record
character(len=80) :: inrec2 ! left adjusted input record
character(len=len(group)) :: lc_group
!---------------------------------------------------------------------------
len_grp = len_trim(group)
lc_group = to_lower
(group)
ios = 0
do while (ios <= 0)
read(unit, '(a)', iostat=ios, end=100) inrec
if (ios <= 0) then ! ios < 0 indicates an end of record condition
! look for group name in this record
! remove leading blanks
inrec2 = adjustl(inrec)
! check for leading '&'
if (inrec2(1:1) == '&') then
! check for case insensitive group name
if (trim(lc_group) == to_lower
(inrec2(2:len_grp+1))) then
! found group name. backspace to leave file position at this record
backspace(unit)
status = 0
return
end if
end if
end if
end do
100 continue ! end of file processing
status = -1
end subroutine find_group_name
end module namelist_utils