Given my interest in extending the life of my SD cards and hard drives as much as possible, I’m surprised I haven’t come across /dev/shm before. In a word it’s a world-accessible RAM scratchpad, which seems baked right into POSIX, so that virtually every Unix system already has it mounted as a tmpfs by default:
1 2 ❯ mount | grep '/dev/shm' tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev,inode64) Today’s lucky 10,000, indeed.
I thought that /dev/shm was strictly for shm_open() but it seems that all that does is open a file in /dev/shm anyway.