GET_COMMAND_ARGUMENT (The GNU Fortran Compiler)

### 8.129 `GET_COMMAND_ARGUMENT` — Get command line arguments ¶

Synopsis:

  `CALL GET_COMMAND_ARGUMENT(NUMBER [, VALUE, LENGTH, STATUS])`

Description:

  Retrieve the NUMBER-th argument that was passed on the command line when the containing program was invoked.

Class:

  Subroutine

Arguments:

  NUMBER | Shall be a scalar of type `INTEGER` and of default kind, NUMBER \geq 0
  VALUE | (Optional) Shall be a scalar of type `CHARACTER` and of default kind.
  LENGTH | (Optional) Shall be a scalar of type `INTEGER` and of default kind.
  STATUS | (Optional) Shall be a scalar of type `INTEGER` and of default kind.

Return value:

  After `GET_COMMAND_ARGUMENT` returns, the VALUE argument holds the NUMBER-th command line argument. If VALUE cannot hold the argument, it is truncated to fit the length of VALUE. If there are less than NUMBER arguments specified at the command line, VALUE is filled with blanks. If NUMBER = 0, VALUE is set to the name of the program (on systems that support this feature). The LENGTH argument contains the length of the NUMBER-th command line argument. If the argument retrieval fails, STATUS is a positive number; if VALUE contains a truncated command line argument, STATUS is -1; and otherwise the STATUS is zero.

Example:

      PROGRAM test_get_command_argument
        INTEGER :: i
        CHARACTER(len=32) :: arg

        i = 0
        DO
          CALL get_command_argument(i, arg)
          IF (LEN_TRIM(arg) == 0) EXIT

          WRITE (*,*) TRIM(arg)
          i = i+1
        END DO
      END PROGRAM

Standard:

  Fortran 2003 and later

See also:

  `GET_COMMAND` — Get the entire command line,
  `COMMAND_ARGUMENT_COUNT` — Get number of command line arguments