Last version:
FLUKA 2021.2.5, February 18th 2022
(last respin )
flair-2.3-0b 30-Jul-2021


-- Fluka Release
( 18.01.2022 )

FLUKA 2021.2.5 has been released.

font_small font_med font_big print_ascii

[ <--- prev -- ]  [ HOME ]  [ -- next ---> ]

[ full index ]


defines input/output files to be connected at run-time

     WHAT(1) > 0. : logical unit number of a FORMATTED file to be opened
             < 0. : logical unit number of an UNFORMATTED file to be

             Default : no default (WHAT(1) must not be = 0.)

     WHAT(2-6)    : not used

     SDUM = NEW      : the file is opened with status 'NEW'
          = OLD      : the file is opened with status 'OLD'
          = UNKNOWN  : the file is opened with status 'UNKNOWN'
          = READONLY : the file is opened with status 'OLD' and (only
                       on VAX VMS/OpenVMS) in mode 'READONLY'
          = SCRATCH  : the file is opened with status 'SCRATCH'

          Default: SDUM = OLD if |WHAT(1)| = 9, 12, 13, 14
                        = NEW otherwise

If SDUM is not = SCRATCH, the name of the file to be opened must be given in the card which immediately follows.

     Default (option OPEN not given): no file is opened at run time. In
             this case the I/O files must be pre-connected via ASSIGN on
             VAX VMS/OpenVMS (see (3)). On UNIX and Linux, the rfluka
             script provided with the FLUKA code creates the necessary
             symbolic links. On some UNIX systems (e.g. HPUX-9),
             OPEN MUST be given in any case for the data files.


  • 1) The input/output files used by FLUKA are of several kinds:

  • Standard input (logical unit 5) and standard output (logical unit 11) must be redirected via < and > (on UNIX and Linux), or pre-connected via FILEDEF, ASSIGN, etc. on other systems.
  • cross section unformatted data files (logical unit numbers 9, 13 and 14) can be opened with the OPEN option (SDUM = OLD or READONLY), or can be pre-connected (on most UNIX systems,
    preconnection is obtained by means of symbolic links).
    If OPEN is used, the full file name must be given in the card which follows.
  • Scratch files (unit 8 for EMF auxiliary output and unit 16 for Combinatorial Geometry working space) can also be OPENed (with SDUM = SCRATCH) or pre-connected (not on UNIX).
    No file name card must be given for scratch files.
  • The "next seeds" file from the random number generator (logical unit number 2) can be opened by any of the three ways described above (i.e. by OPEN, by pre-connection or automatically) on any of the supported systems.
  • Error message file (logical unit number 15) and estimator output files (created by scoring options such as USRBIN, USRBDX, DETECT etc.):
  • On UNIX systems, they can either be opened by the user (with option OPEN, SDUM = NEW or UNKNOWN and file name given on the next card) or automatically by the program with a default name of the form or, where xxx is the logical unit number.
  • On VAX VMS/OpenVMS, all the three possibilities are available:
    pre-connection, OPEN option and automatic opening with a default name of the form FORxxx.DAT.

  • Files created by user-written code: all the three possibilities are available. Of course, a Fortran statement OPEN can also be used in this case.

  • 2) It is possible to pre-connect some of the files and to OPEN others.


 *   opening the file with the random number seeds for the next run
 OPEN              2.                                                  NEW
 *   the neutron cross section file
 OPEN             -9.                                                  READONLY
 *   the working space for Combinatorial Geometry
 OPEN             16.                                                  SCRATCH

© FLUKA Team 2000–2022

Informativa cookies