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)

     Page 1                       Plan 9            (printed 12/21/24)