MEMFS(4) MEMFS(4)
NAME
memfs - mount a heap based filesystem
SYNOPSIS
memfs [-s] [-rab] [-m size] [mountpoint]
DESCRIPTION
Memfs mounts a newly created heap-based filesystem on the
given mountpoint directory (default /tmp).
The filesystem is entirely maintained in memory, no external
storage is used. File data is allocated in 512 byte blocks.
If a maximum size is specified, the actual maximum is
rounded down to the nearest whole number of blocks:
actualsize := (size / 512) * 512;
The root of the filesystem is owned by the user who invoked
memfs and is created with Read, Write and Execute permis-
sions for the owner and Read and Execute permissions for
everyone else (8r755).
OPTIONS
-s Serve styx on file descriptor 0. The mountpoint and
other mount options are ignored.
-r The default option. The old mountpoint directory
becomes a union directory consisting of just the root
of the new filesystem.
-a Add the root of the new filesystem to the end of the
union directory represented by the mountpoint direc-
tory.
-b Add the root of the new filesystem to the beginning of
the union directory represented by the mountpoint
directory.
SOURCE
/appl/cmd/memfs.b
SEE ALSO
ramfile(4)
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