.\" Copyright (c) 1983 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)quotactl.2	6.1 (Berkeley) %G%
.\"
.TH QUOTA 2 ""
.UC 5
.SH NAME
quota \- manipulate disk quotas
.SH SYNOPSIS
.nf
.B #include <sys/quota.h>
.PP
.B quota(cmd, uid, arg, addr)
.B int cmd, uid, arg;
.B caddr_t addr;
.fi
.SH DESCRIPTION
The
.I quota
call manipulates disk quotas for file systems
which have had quotas enabled with
.IR setquota (2).
The
.I cmd
parameter indicates a command to be applied to
the user ID
.IR uid .
.I Arg
is a command specific argument and
.I addr
is the address of an optional, command specific, data structure
which is copied in or out of the system.  The interpretation of
.I arg
and
.I addr
is given with each command below.
.TP
Q_SETDLIM
Set disc quota limits and current usage for the user with ID
.IR uid .
.I Arg
is a major-minor device indicating a particular file system.
.I Addr
is a pointer to a struct dqblk structure (defined in 
.RI < sys/quota.h >).
This call is restricted to the super-user.
.TP
Q_GETDLIM
Get disc quota limits and current usage for the user with ID
.IR uid .
The remaining parameters are as for Q_SETDLIM.
.TP
Q_SETDUSE
Set disc usage limits for the user with ID
.IR uid .
.I Arg
is a major-minor device indicating a particular file system.
.I Addr
is a pointer to a struct dqusage structure (defined in
.RI < sys/quota.h >).
This call is restricted to the super-user.
.TP
Q_SYNC
Update the on-disc copy of quota usages.
The
.IR uid ,
.IR arg ,
and
.I addr 
parameters are ignored.
.TP
Q_SETUID
Change the calling process's quota limits to those of the
user with ID
.IR uid .
The 
.I arg
and
.I addr
parameters are ignored.  This call is restricted to the super-user.
.TP
Q_SETWARN
Alter the disc usage warning limits for the user with ID
.IR uid .
.I Arg
is a major-minor device indicating a particular file system.
.I Addr
is a pointer to a struct dqwarn structure (defined in
.RI < sys/quota.h >).
This call is restricted to the super-user.
.TP
Q_DOWARN
Warn the user with user ID
.I uid
about excessive disc usage.
This call causes the system to check its current disc usage
information and print a message on the terminal of
the caller for each file system on which the user is over quota.
If the
.I arg
parameter is specified as NODEV, all file systems which have
disc quotas will be checked.  Otherwise, 
.I arg
indicates a specific major-minor device to be checked.
This call is restricted to the super-user.
.SH "RETURN VALUE"
A successful call returns 0 and, possibly, more
information specific to the 
.I cmd
performed; when an error occurs, the value \-1
is returned and 
.I errno
is set to indicate the reason.
.SH ERRORS
A
.I quota
call will fail when one of the following occurs:
.TP 15
[EINVAL]
.I Cmd
is invalid.
.TP 15
[ESRCH]
No disc quota is found for the indicated user.
.TP 15
[EPERM]
The call is priviledged and the caller was not the super-user.
.TP 15
[EINVAL]
The 
.I arg
parameter is being interpreted as a major-minor
device and it indicates an unmounted file system.
.TP 15
[EFAULT]
An invalid
.I addr
is supplied; the associated structure could not be copied in or out
of the kernel.
.TP 15
[EUSERS]
The quota table is full.
.SH "SEE ALSO"
setquota(2), quotaon(8), quotacheck(8)
.SH BUGS
There should be someway to integrate this call with the resource
limit interface provided by
.IR setrlimit (2)
and
.IR getrlimit (2).
.PP
The Australian spelling of
.I disk
is used throughout the quota facilities in honor of
the implementors.