non-persistant storage?

[Ulli Horlacher]

On Thu 2019-12-12 (17:06), L A Walsh wrote:

> On 2019/12/12 13:40, Eliot Moss wrote:
> 
> > Ah!  I think what you want is a tmpfs or ramfs.
> > Not sure if cygwin supports that ...
> >   
> ----
>     Easiest thing might be to use /dev/shm. I used it during
> development to store intermediate data that was later to be
> transfered via a fifo...
> 
> Basically check for existence of "/dev/shm" (exists on my cygwin).
> if "tmp" didn't already exist, create it w/options similar to
> /tmp (only owner can delete/edit):
> 
> mkdir -m 1777 /tmp/shm/tmp
> 
> 
> **Warning, "writes" to /dev/shm/tmp (or /dev/mem) can fill up
> your system's memory, so its only good for "small files"
> (small being well under your system's free memory amount).

This is true for Linux, but not for cygwin, where /dev/shm is ntfs on disk: 

~: uname -a
CYGWIN_NT-10.0 VD-TIK-12 3.0.7(0.338/5/3) 2019-04-30 18:08 x86_64 Cygwin
~: df -TH /dev/shm

Filesystem     Type  Size  Used Avail Use% Mounted on
C:/cygwin64    ntfs   34G   25G  8.9G  74% /

Its content is still there after a reboot and I can see it with the windows
explorer:

https://fex.belwue.de/fop/dyQzlG1x/X-20191213103905.png


-- 
Ullrich Horlacher              Server und Virtualisierung
Rechenzentrum TIK         
Universitaet Stuttgart         E-Mail: horlacher@tik.uni-stuttgart.de
Allmandring 30a                Tel:    ++49-711-68565868
70569 Stuttgart (Germany)      WWW:    http://www.tik.uni-stuttgart.de/
REF:<5DF2E42A.7020200@tlinx.org>

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