There's always the BFI method: start at 0, create a filehandle for that descriptor, close it, increment and repeat until you reach a maximum (there's probably a way to tickle the maximum possible file descriptor number out of POSIX but I can't recall it offhand and my copy of APUE isn't readily available). 

use constant MAX_DESCRIPTORS => 255;
for my $fd_no ( 0 .. MAX_DESCRIPTORS() ) {
  open( my $fh, ">>&=", $fd_no ) or warn "Can't dup FD $fd_no: $!\n";
  close( $fh );
}

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Update: Dur, never mind me. The correct mechanism is POSIX::close as is mentioned below, not dup'ing. MENTAL NOTE: NO POSTING BEFORE CAFFEINE . . .

The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re: how to close all files by Fletch
in thread how to close all files by eleron

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