in reply to Local tied FILEHANDLE

"do not work" is never a good description of a problem (if you want help with the problem). Please do what you should always do: Reduce the script to a very, very small script that demonstrates the problem and post the exact script, the exact input and output (including any error messages), and exactly what seems wrong about it to you. (and use strict.pm; and -w)

Anyway, I think local(*STDOUT) would be exactly what you'd want here.

The other suggestion of open(OLDOUT, ">&STDOUT"); doesn't seem like a useful thing to me when dealing with a tied file handle. It is execellent advise when dealing with non-tied file handles, though.

        - tye (but my friends call me "Tye")

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Re: (tye)Re: Local tied FILEHANDLE
by gildir (Pilgrim) on Jan 05, 2001 at 19:25 UTC
    Well then, were it is:

    Script: 

    use strict;

my $bar = tie(*STDOUT, 'Bar');

print "Before\n";
test();
print "After\n";

untie(*STDOUT);

sub test {
        local(*STDOUT);

        my $foo = tie(*STDOUT, 'Foo');
        print "In medias res\n";
        untie(*STDOUT);
}

package Foo;

sub TIEHANDLE {
        my ($class) = @_;
        return bless({},$class);
}

sub PRINT {
        my ($self) = shift;
        print STDERR ("Foo::PRINT: ",@_);
}

package Bar;

sub TIEHANDLE {
        my ($class) = @_;
        return bless({},$class);
}

sub PRINT {
        my ($self) = shift;
        print STDERR ("Bar::PRINT: ",@_);
}
    Output: 
    Bar::PRINT: Before
Foo::PRINT: In medias res
After
    Expected output: 
    Bar::PRINT: Before
Foo::PRINT: In medias res
Bar::After

    It seems like STDOUT is retied to Foo and then untied. local(*STDOUT) has no effect here. Why?

[reply]
      If it isn't could someone explain the following short program to me? My expectation is that after calling local the original handle should be untouched by anything that you do. This emphatically is not happening: 
      test(1);
test(2);

sub test {
    my $iter = shift;
    my $fh = \*STDOUT;
    print $fh "Before local $iter\n";
    local *STDOUT;
    print $fh "Before tying $iter\n";
    tie (*STDOUT, 'Foo', $iter);
    print $fh "After tying $iter\n";
}

package Foo;

sub TIEHANDLE {
    my ($class) = shift;
    return bless([shift],$class);
}

sub PRINT {
    my ($self) = shift;
    print STDERR ("Foo::PRINT (tie $self->[0]): ",@_);
}

      [download]
[reply]
[d/l]
      Please use code tags. They are not just for formatting, they also allow people to easily download your code and run it.

      Given an IE bug on the machine I am on right now, this is inconvenient for me, so I am unable to test my guesses as to what your problem might be...

[reply]

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