Re: Detecting filehandles

In article <48mdnTde3IAuLM_ZnZ2dnUVZ_s6dnZ2d@xxxxxxxxxxxx>,
"Subotai" <subotai@xxxxxxx> wrote:

Is there a way to detect if an argument you are passed in a subroutine is a
filehandle? For instance:

open(FILE, '/file');
foo(\*FILE);
foo($someotherarg);

sub foo {
$arg = shift;
#### do some check on $arg to see if it is a filehandle or a normal scalar
}

Look at the 'openhandle' function in Scalar::Util.

Also if you have an open filehandle, is there a way to see what file it is
referencing? For instance if you open the file "/foo", is there anyway to
get "/foo" from the filehandle? I know with the fileno() call you can get
the file descriptor, is there anyway you could use that to lookup that
information? I don't think there is but I want to be 100% sure.

I don't believe there is, either. It would be difficult to impossible
to implement under Unix, because a file is one thing and its name is
something else; in fact a file can have multiple names (directory
entries), so how would you choose which one is "the" file?
--
Kevin Michael Vail | a billion stars go spinning through the night,
kevin@xxxxxxxxxx   | blazing high above your head.
 . . . . . . . . . | But _in_ you is the presence that
  . . . . . . . .  | will be, when all the stars are dead.
 . . . . . . . . . |     (Rainer Maria Rilke)

.

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