Tricky. Here's a non-portable way to do it.

First, get a list of file descriptors. On many Unix systems, you can use lsof for that, or look in the /proc filesystem (which will have a different format on different OSses). On my system, I can do: 

  my @fds = `ls /proc/$$/fd`;
  chomp @fds;

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Now you have a list of filedescriptors. Unfortunally, you cannot use Perl's close with just the filedescriptor. But don't despair, Perl does give you access to the system calls. syscall is unknown to many people, but it's powerful. On a Unix system, the following ought to work: 
    require 'syscall.ph';  # May have to run h2ph first.
    for my $fd (@fds) {
        syscall(&SYS_close, $fd) == -1 or die $!;
    }

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Frankly, I rather keep track of my filehandles. ;-)

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

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