On Friday, 11 December 2020 at 16:49:18 UTC, Adam D. Ruppe wrote: > libc-2.30.so The bug was fixed in 2.28 IIRC. > so i guess i have the fixed libc. Can you confirm what version > you have? Various. I tested the code on a machine running the yet EOL CENTOS-6 having glibc 2.12.