All standard indicate exit should terminate the whole process/task: https://pubs.opengroup.org/onlinepubs/007904975/functions/exit.html https://en.cppreference.com/w/c/program/exit https://linux.die.net/man/2/exit so let's remove the option and trust the caller know the difference: 1.exit terminate all threads belong the current process/task 2.pthread_exit only terminate the current(main/pthread) thread Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com> Change-Id: I2950ddee3d471272bb9570782f1cd4af33513d57