quota.2

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 2 代码 · 共 166 行

.\" SCCSID: @(#)quota.2	8.1	9/11/90
.TH quota 2
.SH Name
quota \- manipulate disk quotas
.SH Syntax
.nf
.B #include <sys/types.h>
.B #include <sys/param.h>
.B #include <sys/quota.h>
.PP
.B quota(cmd, uid, arg, addr)
.B int cmd, uid, arg;
.B caddr_t addr;
.fi
.SH Description
.NXR "quota system call"
.NXAM "quota system call" "quotacheck command"
.NXR "disk quota" "manipulating"
The
.PN quota
call manipulates disk quotas for file systems
that have had quotas enabled with 
.PN setquota .
The
.I cmd
parameter indicates a command in the following list that is applied to
the user ID
.IR uid .
The
.I arg
parameter 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 in the list that follows:
.NXR "quota system call" "command list"
.TP
Q_SETDLIM
Set disk quota limits and current usage for the user with ID
.IR uid .
The
.I arg
parameter is a major-minor device indicating a particular file system.
The
.I addr
parameter is a pointer to a struct dqblk structure,
defined in <sys/quota.h>.
Only the superuser can issue this call.  
.TP
Q_GETDLIM
Get disk quota limits and current use for the user with ID
.IR uid .
The remaining parameters are identical to the Q_SETDLIM command
parameters.
.TP
Q_SETDUSE
Set disk use limits for the user with ID
.IR uid .
The
.I arg
parameter is a major-minor device indicating a particular file system.
The
.I addr
is a pointer to a struct
dqusage structure, defined in <sys/quota.h>.
Only the superuser can issue this call.
.TP
Q_SYNC
Update the on-disk copy of quota uses.
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.  Only the superuser can issue this call.
.TP
Q_SETWARN
Alter the disk usage warning limits for the user with ID
.IR uid .
The
.I arg
is a major-minor device indicating a particular file system.
The
.I addr
parameter is a pointer to a struct dqwarn structure, which is 
defined in <sys/quota.h>.
Only the superuse can issue this call.
.TP
Q_DOWARN
Warn the user with user ID
.I 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
.I arg
parameter is specified as NODEV, all file systems that have
disk quotas are checked.  Otherwise, 
.I arg
indicates a specific major-minor device to be checked.
Only the superuser can issue this call.
.SH Return Values
A successful call returns 0 and, possibly, more
information specific to the command specified in the 
.I cmd
parameter; when an error occurs, the value \-1
is returned and the global variable
.I errno
is set to indicate the reason.
.SH Diagnostics
.NXR "quota system call" "diagnostics"
A
.I quota
call fails when one of the following occurs:
.TP 15
[EINVAL]
The kernel has not been compiled with the QUOTA option.
.TP 15
[EINVAL]
The
.I cmd
parameter is invalid.
.TP 15
[ESRCH]
No disk quota is found for the indicated user.
.TP 15
[EPERM]
Only the superuser can issue the call and the caller is not the
superuser.
.TP 15
[ENODEV]
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
parameter 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
.MS setquota 2, 
.MS quotacheck 8, 
.MS quotaon 8
.br
"Disk Quotas in a UNIX Environment",
.I ULTRIX Supplementary Documents, Volume 3:System Manager