create a ramdisk in C++ on linux - c++

Question

I need to make a ramfs an mount it to an directory in linux using c++. I want to make it like a user (no sudo).
I need to call an application on a file that i created and it will be often. Writing it to HDD is very slow.
I found just:
system("mkdir /mnt/ram");
system("mount -t ramfs -o size=20m ramfs /mnt/ram");
but that is not good. I want to be a regular user, and command mount can be called just as root.
what can i do?

Answer 1

For a userspace ramfs solution, you can use python-fuse-ramfs.

Answer 2

I checket if /tmp is a ramfs, but it is not. It creates files on the HDD. but when i run df -h it outputs:
rootfs 25G 9,4G 15G 40% /
devtmpfs 1,9G 0 1,9G 0% /dev
tmpfs 1,9G 1,6G 347M 83% /dev/shm
tmpfs 1,9G 1,3M 1,9G 1% /run
/dev/mapper/vg_micro-root 25G 9,4G 15G 40% /
tmpfs 1,9G 0 1,9G 0% /sys/fs/cgroup
tmpfs 1,9G 0 1,9G 0% /media
/dev/mapper/vg_micro-stack 289G 191M 274G 1% /stack
/dev/mapper/vg_micro-home 322G 40G 266G 14% /home
/dev/sda2 485M 89M 371M 20% /boot
/dev/sda1 200M 19M 182M 10% /boot/efi
This means that tmpfs (ramdisks) are: /dev/shm, /run, /sys/fs/cgroup and /media. But only one of this is meant to be a temporary ramdisk for comunication between processes, using files. Here is the /dev/shm description and usage. The only thing is that tmpfs will not grow dynamically, but for my purposes it will be enough (20MB - 1GB).