What makes you think you need to do anything special?

The following starts a thread logging to STDERR (which is redirected to 'oldLog') once per second. The main thread then sleeps, logs once, reopens STDERR to 'aNewLog'; logs once more then sleeps 3 before ending. You'll see that there is output from both threads in 'oldLog', and also from both in 'aNewLog': 

C> perl -Mthreads -E"
async{ warn threads->tid while sleep 1}; 
sleep 1; 
warn threads->tid; 
open STDERR, '>', 'aNewLog';  
warn threads->tid; 
sleep 3
" 2>oldLog

C> type oldLog
1 at -e line 1.
0 at -e line 1.

C> type aNewLog
0 at -e line 1.
1 at -e line 1.
1 at -e line 1.
1 at -e line 1.
Perl exited with active threads:
        1 running and unjoined
        0 finished and unjoined
        0 running and detached

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP an inspiration; A true Folk's Guy

In reply to Re: perl file handle share thread by BrowserUk
in thread perl file handle share thread by Anonymous Monk

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