RAMDISKADM(1M)RAMDISKADM(1M)NAMEramdiskadm - administer ramdisk pseudo device
SYNOPSIS
/usr/sbin/ramdiskadm -a name size [g | m | k | b]
/usr/sbin/ramdiskadm -d name
/usr/sbin/ramdiskadm
DESCRIPTION
The ramdiskadm command administers ramdisk(7D), the ramdisk driver.
Use ramdiskadm to create a new named ramdisk device, delete an existing
named ramdisk, or list information about existing ramdisks.
Ramdisks created using ramdiskadm are not persistent across reboots.
OPTIONS
The following options are supported:
-a name size
Create a ramdisk named name of size size and its corre‐
sponding block and character device nodes.
name must be composed only of the characters a-z, A-Z,
0-9, _ (underbar), and - (hyphen), but it must not
begin with a hyphen. It must be no more than 32 charac‐
ters long. Ramdisk names must be unique.
The size can be a decimal number, or, when prefixed
with 0x, a hexadecimal number, and can specify the size
in bytes (no suffix), 512-byte blocks (suffix b), kilo‐
bytes (suffix k), megabytes (suffix m) or gigabytes
(suffix g). The size of the ramdisk actually created
might be larger than that specified, depending on the
hardware implementation.
If the named ramdisk is successfully created, its block
device path is printed on standard out.
-d name
Delete an existing ramdisk of the name name. This com‐
mand succeeds only when the named ramdisk is not open.
The associated memory is freed and the device nodes are
removed.
You can delete only ramdisks created using ramdiskadm.
It is not possible to delete a ramdisk that was created
during the boot process.
Without options, ramdiskadm lists any existing ramdisks, their sizes
(in decimal), and whether they can be removed by ramdiskadm (see the
description of the -d option, above).
EXAMPLES
Example 1 Creating a 2MB Ramdisk Named mydisk
# ramdiskadm-a mydisk 2m
/dev/ramdisk/mydisk
Example 2 Listing All Ramdisks
# ramdiskadm
Block Device Size Removable
/dev/ramdisk/miniroot 134217728 No
/dev/ramdisk/certfs 1048576 No
/dev/ramdisk/mydisk 2097152 Yes
EXIT STATUSramdiskadm returns the following exit values:
0
Successful completion.
>0
An error occurred.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬─────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼─────────────────┤
│Interface Stability │ Evolving │
└────────────────────┴─────────────────┘
SEE ALSOattributes(5), ramdisk(7D)NOTES
The abilities of ramdiskadm and the privilege level of the person who
uses the utility are controlled by the permissions of /dev/ramdiskctl.
Read access allows query operations, for example, listing device infor‐
mation. Write access is required to do any state-changing operations,
for example, creating or deleting ramdisks.
As shipped, /dev/ramdiskctl is owned by root, in group sys, and mode
0644, so all users can do query operations but only root can perform
state-changing operations. An administrator can give write access to
non-privileged users, allowing them to add or delete ramdisks. However,
granting such ability entails considerable risk; such privileges should
be given only to a trusted group.
Mar 25, 2003 RAMDISKADM(1M)
