What is /dec/shm? Is is kind of a RAM drive? I have had an entry in my df listing and /etc/fstab for it for quite a while. I was just wondering what it was...
Later Mike
On Tue, 2004-07-20 at 23:02, Mike Pfaiffer wrote:
What is /dec/shm? Is is kind of a RAM drive? I have had an entry in my df
[sean@bob sean]$ mount ... none on /dev/shm type tmpfs (rw)
[sean@bob sean]$ locate tmpfs /usr/src/linux-2.4.22-1.2188.nptl/include/config/tmpfs.h /usr/src/linux-2.4.22-1.2197.nptl/Documentation/filesystems/tmpfs.txt /usr/src/linux-2.4.22-1.2197.nptl/fs/intermezzo/journal_tmpfs.c
[sean@bob sean]$ more /usr/src/linux-2.4.22-1.2197.nptl/Documentation/filesystems/tmpfs.txt Tmpfs is a file system which keeps all files in virtual memory. ...
Who uses it? shm is an acronym for SHared Memory. From the shm_open(3) man page there is a note:
The POSIX shared memory object implementation on Linux 2.4 makes use of a dedicated file system, which is normally mounted under /dev/shm.
"UNIX Network Programming" by Stevens explains shm and other forms of IPC far better than I could ever hope to.
Sean
On July 21, 2004 06:49 am, Sean A. Walberg wrote:
On Tue, 2004-07-20 at 23:02, Mike Pfaiffer wrote:
<snip>
Thanks. I'm still not quite sure what's up. That's OK though. Now I have a vague idea what it is. I was kind of worried it was something about half the size of my physical memory. The important thing is it's supposed to be there. ;-)
Later Mike
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Mike Pfaiffer -
Sean A. Walberg