quotactl(2)quotactl(2)NAMEquotactl - manipulate disk quotas
SYNOPSIS
#include <sys/types.h>
#include <sys/quota.h>
int quotactl (int cmd, char *special, int uid, caddr_t addr);
DESCRIPTION
The quotactl(2) call manipulates disk quotas for local EFS and XFS
filesystems. cmd indicates a command to be applied to the user ID uid.
special is a pointer to a null-terminated string containing the pathname
of the block special device for the filesystem being manipulated. The
block special device must be mounted as an EFS or XFS filesystem (see
mount(2)). addr is the address of an optional, command specific data
structure which is copied in or out of the system. The interpretation of
addr is given with each command below.
Q_QUOTAON
Turn on quotas for a filesystem. In EFS, addr points to the pathname
of the file containing the quotas for the filesystem. This quotas
file must exist. In contrast, XFS provides the ability to turn
on/off quota limit enforcement with quota accounting. Therefore, XFS
expects the addr to be a pointer to an unsigned int that contains
the flags XFS_QUOTA_UDQ_ACCT and/or XFS_QUOTA_UDQ_ENFD defined in
<sys/quota.h>. This call is restricted to the superuser.
Q_QUOTAOFF
Turn off quotas for a filesystem. As in Q_QUOTAON, XFS filesystems
expect a pointer to an unsigned int that specifies whether quota
accounting and/or limit enforcement need to be turned off. The uid
field is ignored. EFS ignores the addr field as well. This call is
restricted to the superuser.
Q_GETQUOTA
Get disk quota limits and current usage for user uid. addr is a
pointer to a dqblk structure (defined in <sys/quota.h> ). Only the
superuser may get the quotas of a user other than himself.
Q_SETQUOTA
Set disk quota limits and current usage for user uid. addr is a
pointer to a dqblk structure (defined in <sys/quota.h> ). This call
is restricted to the superuser, and is not supported in XFS.
Q_SETQLIM
Set disk quota limits for user uid. addr is a pointer to a dqblk
structure (defined in <sys/quota.h> ). This call is restricted to
the superuser.
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Q_SYNC
Update the on-disk copy of quota usages for an EFS filesystem. If
special is null then all filesystems with active quotas are sync'ed.
addr and uid are ignored. This option is not supported in XFS since
sync(1M) writes quota information to disk as well.
Q_ACTIVATE
If quotas are not already enabled, this call will permit queries and
updates to be made to the quota file without enabling quotas. addr
points to the pathname of the file containing the quotas for the EFS
filesystem. The quota file must exist. This command is not
applicable to XFS filesystems.
Q_XGETQUOTA
Q_XSETQLIM
These are extensions to Q_GETQUOTA and Q_SETQLIM respectively to
support the added functionalities of XFS filesystems. Instead of a
dqblk structure, these commands expect a fs_disk_quota structure
defined in <sys/quota.h>.
Q_GETQSTAT
Returns a fs_quota_stat structure containing XFS filesystem specific
quota information. This is useful in finding out how much space is
spent to store quota information, and also to get quotaon/off status
of a given local XFS filesystem.
Q_QUOTARM
Free the disk space taken by disk quotas. Quotas must have already
been turned off.
RETURN VALUE
Upon successful completion, a value of 0 is returned. Otherwise, a value
of -1 is returned and errno is set to indicate the error.
ERRORS
A quotactl(2) call will fail when one of the following occurs:
EINVAL
cmd is invalid.
ESRCH
Quotas have not been turned on for this filesystem.
EPERM
The call is privileged and the caller was not the superuser.
ENODEV
special is not a mounted EFS or XFS filesystem.
ENOTBLK
special is not a block device.
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EACCES
(Q_QUOTAON) The quota file pointed to by addr exists but is either
not a regular file or is not on the EFS filesystem pointed to by
special or is not owned by root.
ENOSPC
The quota table is full. Doesn't apply to XFS filesystems since XFS
dynamically allocates space for quota information.
EEXIST
Q_QUOTAON attempted on a filesystem where quotas have already been
turned on or Q_QUOTAOFF attempted on a filesystem where quotas have
not been turned on.
ENOENT
The file specified by special or addr does not exist.
EFAULT
addr or special are invalid.
ENOTSUP
cmd is not supported by the given filesystem.
BUGS
XFS currently does not support the Q_GETQUOTA and Q_SETQLIM commands.
EFS does not support commands such as Q_XGETQUOTA and Q_XSETQLIM that
take in a fs_disk_quota structure.
SEE ALSOquota(1), quotacheck(1M), quotaon(1M), mount(2)
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