Dismounts a mounted volume or volume sets.
Format
SYS$DISMOU devnam ,[flags]
C Prototype
int sys$dismou (void *devnam, unsigned int flags);
1 – Arguments
devnam
OpenVMS usage:device_name
type: character-coded text string
access: read only
mechanism: by descriptor-fixed-length string descriptor
Device name of the device to be dismounted. The devnam argument
is the address of a character string descriptor pointing to
the device name string. The string can be either a physical
device name or a logical name. If it is a logical name, it must
translate to a physical device name.
flags
OpenVMS usage:mask_longword
type: longword (unsigned)
access: read only
mechanism: by value
A longword bit vector specifying options for the dismount
operation. The flags argument is a longword bit vector wherein
a bit, when set, selects the corresponding option. Each bit has a
symbolic name; these names are defined by the $DMTDEF macro.
The flags and their meanings are listed in the following table:
Flag Meaning
DMT$M_ABORT The volume is to be dismounted even if
the caller did not mount the volume. If
the volume was mounted with MNT$M_SHARE
specified, $DISMOU dismounts the volume for
all of the users who mounted it.
To specify DMT$M_ABORT, the caller must: (1)
have GRPNAM privilege for a group volume,
(2) have SYSNAM privilege for a system
volume, or (3) either own the volume or have
VOLPRO privilege.
DMT$M_CLUSTER The volume is to be dismounted clusterwide,
that is, from all nodes in the OpenVMS
Cluster system. $DISMOU dismounts the volume
from the caller's node first and then from
every other node in the existing cluster.
DMT$M_CLUSTER dismounts only system or
group volumes. To dismount a group volume
clusterwide, the caller must have GRPNAM
privilege. To dismount a system volume
clusterwide, the caller must have SYSNAM
privilege.
DMT$M_CLUSTER has no effect if the system
is not a member of a cluster. DMT$M_CLUSTER
applies only to disks.
DMT$M_FORCE If connectivity to a device has been lost and
the shadow set is in mount verification, this
flag causes a named shadow set member to be
immediately expelled from the shadow set.
DMT$M_MINICOPY_ $DISMOU takes place, regardless of whether
OPTIONAL minicopy is enabled on the disk.
DMT$M_MINICOPY_ $DISMOU fails if minicopy has not been
REQUIRED enabled on the disk.
DMT$M_NOUNLOAD Specifies that the volume is not to be
physically unloaded after the dismount. If
both the DMT$M_UNLOAD and DMT$M_NOUNLOAD
flags are specified, the DMT$M_NOUNLOAD flag
is ignored. If neither flag is specified,
the volume is physically unloaded, unless
the DMT$M_NOUNLOAD flag was specified on
the $MOUNT system service or the /NOUNLOAD
qualifier was specified on the MOUNT command
when the volume was mounted.
DMT$M_OVR_CHECKS Specifies that the volume should be
dismounted without checking for open files,
spooled devices, installed images, or
installed swap and page files.
DMT$M_UNIT The specified device, rather than the entire
volume set, is dismounted.
DMT$M_UNLOAD Specifies that the volume is to be physically
unloaded after the dismount. If both the
DMT$M_UNLOAD and DMT$M_NOUNLOAD flags
are specified, the DMT$M_NOUNLOAD flag
is ignored. If neither flag is specified,
the volume is physically unloaded, unless
the DMT$M_NOUNLOAD flag was specified on
the $MOUNT system service or the /NOUNLOAD
qualifier was specified on the MOUNT command
when the volume was mounted.