Fellow monks,

I have a need to fork() and then redefine a function within the child, but not the parent. Here's my code.

use warnings;
use strict;

sub foo {
    my $bar = shift;
    print "original foo($bar)\n";
}

if (my $pid = fork()) {
    close PARENT;

    foo('parent');

    close CHILD;
    waitpid($pid, 0);
} else {
    die "cannot fork: $!" unless defined $pid;
    close CHILD;

    # overload the function
    no warnings 'redefine';
    sub foo {
        my $bar = shift;
        print "modified foo($bar)\n";
    }

    foo('child');

    close PARENT;
    exit(0);
}

foo('the end');

[download]
This prints:
modified foo(parent)
modified foo(child)
modified foo(the end)

However, I was hoping that the redefinition of the foo() function would only affect the scope of the child process. In other words, I wanted to get
original foo(parent)
modified foo(child)
original foo(the end)

Is something like this possible?

In reply to Redefining function after fork by gri6507

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