quota(2)quota(2)Namequota - manipulate disk quotas
Syntax
#include <sys/types.h>
#include <sys/param.h>
#include <sys/quota.h>
quota(cmd, uid, arg, addr)
int cmd, uid, arg;
caddr_t addr;
Description
The call manipulates disk quotas for file systems that have had quotas
enabled with The cmd parameter indicates a command in the following
list that is applied to the user ID uid. The arg parameter is a com‐
mand specific argument and addr is the address of an optional, command
specific data structure, which is copied in or out of the system. The
interpretation of arg and addr is given with each command in the list
that follows:
Q_SETDLIM
Set disk quota limits and current usage for the user with ID
uid. The arg parameter is a major-minor device indicating a
particular file system. The addr parameter is a pointer to a
struct dqblk structure, defined in <sys/quota.h>. Only the
superuser can issue this call.
Q_GETDLIM
Get disk quota limits and current use for the user with ID uid.
The remaining parameters are identical to the Q_SETDLIM command
parameters.
Q_SETDUSE
Set disk use limits for the user with ID uid. The arg parameter
is a major-minor device indicating a particular file system.
The addr is a pointer to a struct dqusage structure, defined in
<sys/quota.h>. Only the superuser can issue this call.
Q_SYNC Update the on-disk copy of quota uses. The uid, arg, and addr
parameters are ignored.
Q_SETUID
Change the calling process's quota limits to those of the user
with ID uid. The arg and addr parameters are ignored. Only the
superuser can issue this call.
Q_SETWARN
Alter the disk usage warning limits for the user with ID uid.
The arg is a major-minor device indicating a particular file
system. The addr parameter is a pointer to a struct dqwarn
structure, which is defined in <sys/quota.h>. Only the superuse
can issue this call.
Q_DOWARN
Warn the user with user ID uid about excessive disk use. This
call causes the system to check its current disk use information
and print a message on the terminal of the caller for each file
system on which the user is over quota. If the arg parameter is
specified as NODEV, all file systems that have disk quotas are
checked. Otherwise, arg indicates a specific major-minor device
to be checked. Only the superuser can issue this call.
Return Values
A successful call returns 0 and, possibly, more information specific to
the command specified in the cmd parameter; when an error occurs, the
value -1 is returned and the global variable errno is set to indicate
the reason.
Diagnostics
A quota call fails when one of the following occurs:
[EINVAL] The kernel has not been compiled with the QUOTA option.
[EINVAL] The cmd parameter is invalid.
[ESRCH] No disk quota is found for the indicated user.
[EPERM] Only the superuser can issue the call and the caller is
not the superuser.
[ENODEV] The arg parameter is being interpreted as a major-minor
device, and it indicates an unmounted file system.
[EFAULT] An invalid addr parameter is supplied; the associated
structure could not be copied in or out of the kernel.
[EUSERS] The quota table is full.
See Also
"Disk Quotas in a UNIX Environment", ULTRIX Supplementary Documents,
Volume 3:System Manager
quota(2)