ISATTY (The GNU Fortran Compiler)

### 8.167 `ISATTY` — Whether a unit is a terminal device ¶

Synopsis:

  `RESULT = ISATTY(UNIT)`

Description:

  Determine whether a unit is connected to a terminal device.

Class:

  Function

Arguments:

  UNIT | Shall be a scalar `INTEGER`.

Return value:

  Returns `.TRUE.` if the UNIT is connected to a terminal device, `.FALSE.` otherwise.

Example:

      PROGRAM test_isatty
        INTEGER(kind=1) :: unit
        DO unit = 1, 10
          write(*,*) isatty(unit=unit)
        END DO
      END PROGRAM

Standard:

  GNU extension

See also:

  `TTYNAM` — Get the name of a terminal device