ACCESS Function

Portability Function: Determines if a file exists and how it can be accessed.

Module

USE IFPORT

Syntax

result=ACCESS(name,mode)

name

(Input) Character*(*). Name of the file whose accessibility is to be determined.

mode

(Input) Character*(*). Modes of accessibility to check for. Must be a character string of length one or greater containing only the characters "r", "w", "x", or "" (a blank). These characters are interpreted as follows.

Character	Meaning
r	Tests for read permission
w	Tests for write permission
x	Tests for execute permission. On Windows* systems, the extension of `name` must be .COM, .EXE, .BAT, .CMD, .PL, .KSH, or .CSH.
(blank)	Tests for existence

The characters within mode can appear in any order or combination. For example, wrx and r are legal forms of mode and represent the same set of inquiries.

Results

The value of the result is INTEGER(4). It is zero if all inquiries specified by mode are true. If either argument is invalid, or if the file cannot be accessed in all of the modes specified, one of the following error codes is returned:

EACCES: Access denied; the file's permission setting does not allow the specified access
EINVAL: The mode argument is invalid
ENOENT: File or path not found

For a list of error codes, see IERRNO.

The name argument can contain either forward or backward slashes for path separators.

On Windows* systems, all files are readable. A test for read permission always returns 0.

Compatibility

CONSOLE STANDARD GRAPHICS QUICKWIN GRAPHICS WINDOWS DLL LIB

Example

! checks for read and write permission on the file "DATAFILE.TXT"

J = ACCESS ("DATAFILE.TXT", "rw")

PRINT *, J

! checks whether "DATAFILE.TXT" is executable. It is not, since

! it does not end in .COM, .EXE, .BAT, or .CMD

J = ACCESS ("DATAFILE.TXT","x")