PK1>c2*sE thread_group.hppUTԜMWmo0>iJƖnJc/4XE|I mʘo& ݨKs1EBx}q1$o?ˣwכp\ѽpc5g! 6Fu) jg°m̴R3bXL\D~=_kPU^o2xܒ'u9v55b vw_#ac) ONSs'Y MAagch31J-F6! _G=:Di伉 z?|"iR@2r8^>D|IASf77n67?@/T)WԲ~?McO@*pZT uv:=7'16J[~1o".w iW?>:Ĺ93Or7%2ⶳD#c2*sE Gthread_group.hppUTԜMI revised the solution to the problem. The join all method will copy the current thread list. The join all method will then join all the current threads in the list. All modifications to the list will be ignored until join_all exits and is called again. Other solutions are welcome, but this is a classic reader-writer problem.PK