file-io,fortran,gfortran , Accessing open files globally in Fortran


Accessing open files globally in Fortran

Question:

Tag: file-io,fortran,gfortran

Is there any means to accessing (reading, writing to) files that are opened in some other source code by just passing the unit number?


Answer:

Yes, that is possible (for both reading and writing). Here is a short example:

module test_mod
contains

  subroutine myWrite( uFile )
    implicit none
    integer, intent(in) :: uFile

    write(uFile, *) 'Hello world'
  end subroutine
end module

program test
  use test_mod
  implicit none
  integer :: uFile, stat

  open(newunit=uFile, file='test.txt', status='replace', &
       action='write', iostat=stat)
  if(stat.ne.0) return

  call myWrite( uFile )
  close (uFile)
end program

$ cat test.txt 
 Hello world

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