Standard intrinsic module ISO_FORTRAN_ENV

1 Name

iso_fortran_env — standard intrinsic module

2 Usage


(The ',INTRINSIC ::' part is optional.)

3 Synopsis

ISO_FORTRAN_ENV provides named constants describing the Fortran environment.

Storage units are described by CHARACTER_STORAGE_SIZE and NUMERIC_STORAGE_SIZE.

I/O units are described by ERROR_UNIT, INPUT_UNIT and OUTPUT_UNIT.

The RECL= specifier for the INQUIRE and OPEN statements is described by FILE_STORAGE_SIZE.

IOSTAT= return values are described by IOSTAT_END and IOSTAT_EOR. These and many other IOSTAT= return values are provided by the intrinsic module F90_IOSTAT (except that it provides IOSTAT_EOF instead of IOSTAT_END).

4 Parameter Descriptions

  INTEGER,PARAMETER :: character_storage_size = 8
The size of a character storage unit in bits.

  INTEGER,PARAMETER :: error_unit = 0
The standard error reporting unit number.

  INTEGER,PARAMETER :: file_storage_size = 8
The size of a file storage unit (used by RECL= in OPEN and INQUIRE) in bits.

  INTEGER,PARAMETER :: input_unit = 5
The standard input unit number. This is the one used by READ with an asterisk ('*') unit.

  INTEGER,PARAMETER :: iostat_end = -1
The IOSTAT= return value for end of file.

  INTEGER,PARAMETER :: iostat_eor = -2
The IOSTAT= return value for end of record.

  INTEGER,PARAMETER :: numeric_storage_size = BIT_SIZE(0)
The size of a numeric storage unit in bits.

  INTEGER,PARAMETER :: output_unit = 6
The standard output unit number. This is the one used by PRINT, and by WRITE with an asterisk ('*') unit.

5 Files

The source code for this module may be found in the NAG Fortran runtime library directory (usually /usr/local/lib/NAG_Fortran).

6 See Also

f90_iostat(3), nag_modules(3).

7 Bugs

Please report any bugs found to ‘’ or ‘’, along with any suggestions for improvements.

8 Author

Malcolm Cohen, Nihon Numerical Algorithms Group KK, Tokyo, Japan.