Listing the contents of a directory in Fortran

Question

How do I get the contents of a directory in Fortran 95?

Answer 1

There is no concept of a directory in Fortran, as such. It reads files. (There are some processors that don't even have a concept of directory).

With that being said, the easiest way would be with SYSTEM. Depends on what you want with that after ...

Answer 2

To be pedantic, you don't. There's no intrinsic or such in Fortran 95 that helps you.

On a POSIX system and a recent Fortran compiler, you can use ISO_C_BINDING to create interfaces to the POSIX opendir() and readdir() functions (or readdir_r() if you need thread safety), which allow you to iterate over the directory entries.

Answer 3

shure if we have all the files in the 'inFiles' folder, we first find out how many are there and then we read their names into an array, check this out:

  real :: r
  integer :: i,reason,NstationFiles,iStation
  character(LEN=100), dimension(:), allocatable :: stationFileNames

  ! get the files
  call system('ls ./inFiles > fileContents.txt')
  open(31,FILE='fileContents.txt',action="read")
  !how many
  i = 0
  do
   read(31,FMT='(a)',iostat=reason) r
   if (reason/=0) EXIT
   i = i+1
  end do
  NstationFiles = i
  write(verb,'(a,I0)') "Number of station files: " , NstationFiles
  allocate(stationFileNames(NstationFiles))
  rewind(31)
  do i = 1,NstationFiles
   read(31,'(a)') stationFileNames(i)

! write(verb,'(a)') trim(stationFileNames(i)) end do close(31)