MEMFS(4) MEMFS(4)
NAME
memfs - mount a heap based filesystem
SYNOPSIS
memfs [-rab] [size] mountpoint
DESCRIPTION
Memfs mounts a newly created heap-based filesystem on the
given mountpoint directory.
The filesystem is entirely maintained in memory, no external
storage is used. Unless specified by size, the maximum
storage provided by the filesystem is 1 megabyte (1024*1024
bytes). 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 new filesystem is created with Read, Write
and Execute permission for the user only (mode 8r700). The
owner is given by the value returned from /dev/user at the
time of running the command.
Memfs has the following options:
-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.
FILES
/dev/user read to name the owner of the filesystem
/dev/time used to set file creation and modify times
SOURCE
/appl/cmd/memfs.b
SEE ALSO
memfs(2), ramfile(4)
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