NAG FL Interface
x04adf (close)

1 Purpose

x04adf closes a file associated with a given Fortran unit number.

2 Specification

Fortran Interface
Subroutine x04adf ( iounit, ifail)
Integer, Intent (In) :: iounit
Integer, Intent (Inout) :: ifail
C Header Interface
#include <nag.h>
void  x04adf_ (const Integer *iounit, Integer *ifail)
The routine may be called by the names x04adf or nagf_file_close.

3 Description

x04adf is especially useful if the calling language is not Fortran. It closes a file associated with a given Fortran unit number.

4 References

None.

5 Arguments

1: iounit Integer Input
On entry: the Fortran unit number which identifies the file to be closed.
2: ifail Integer Input/Output
On entry: ifail must be set to 0, -1 or 1. If you are unfamiliar with this argument you should refer to Section 4 in the Introduction to the NAG Library FL Interface for details.
For environments where it might be inappropriate to halt program execution when an error is detected, the value -1 or 1 is recommended. If the output of error messages is undesirable, then the value 1 is recommended. Otherwise, if you are not familiar with this argument, the recommended value is 0. When the value -1 or 1 is used it is essential to test the value of ifail on exit.
On exit: ifail=0 unless the routine detects an error or a warning has been flagged (see Section 6).

6 Error Indicators and Warnings

If on entry ifail=0 or -1, explanatory error messages are output on the current error message unit (as defined by x04aaf).
Errors or warnings detected by the routine:
ifail=1
Cannot close file associated with channel value.
ifail=-99
An unexpected error has been triggered by this routine. Please contact NAG.
See Section 7 in the Introduction to the NAG Library FL Interface for further information.
ifail=-399
Your licence key may have expired or may not have been installed correctly.
See Section 8 in the Introduction to the NAG Library FL Interface for further information.
ifail=-999
Dynamic memory allocation failed.
See Section 9 in the Introduction to the NAG Library FL Interface for further information.

7 Accuracy

Not applicable.

8 Parallelism and Performance

x04adf is not threaded in any implementation.

9 Further Comments

None.

10 Example

This example program simply illustrates how to close a file once it has been opened for writing followed by how to close a file once it has been opened for reading.

10.1 Program Text

Program Text (x04adfe.f90)

10.2 Program Data

None.

10.3 Program Results

Program Results (x04adfe.r)