Your bug report

#64773: grep 3.11 -r on 100000+ files fails with "Operation not supported"

which was filed against the grep package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 64773@debbugs.gnu.org.

-- 
64773: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=64773
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