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QUOTACTL(2)                 BSD System Calls Manual                QUOTACTL(2)

NAME
     quotactl -- manipulate filesystem quotas

SYNOPSIS
     #include <sys/types.h>   /* types needed by quota.h */
     #include <sys/quota.h>   /* for disk quotas */

     int
     quotactl(const char *path, int cmd, int id, char *addr);

DESCRIPTION
     The quotactl() call enables, disables and manipulates filesystem quotas.  A quota control command given
     by cmd operates on the given filename path for the given user id.  The address of an optional command
     specific data structure, addr, may be given; its interpretation is discussed below with each command.

     Currently quotas are supported only for the "ffs" and "hfs" filesystems.  A command is composed of a
     primary command (see below) and a command type used to interpret the id.  Types are supported for
     interpretation of user identifiers and group identifiers.  The specific commands are:

     Q_QUOTAON    Enable disk quotas for the filesystem specified by path.  The command type specifies the
                  type of the quotas being enabled.  The addr argument specifies a file from which to take
                  the quotas.  The quota file must exist; it is normally created with the quotacheck(8) pro-gram. program.
                  gram.  The id argument is unused.  Only the super-user may turn quotas on.

     Q_QUOTAOFF   Disable disk quotas for the filesystem specified by path.  The command type specifies the
                  type of the quotas being disabled.  The addr and id arguments are unused.  Only the super-user superuser
                  user may turn quotas off.

     Q_GETQUOTA   Get disk quota limits and current usage for the user or group (as determined by the com-mand command
                  mand type) with identifier id.  Addr is a pointer to a struct dqblk structure.

     Q_SETQUOTA   Set disk quota limits for the user or group (as determined by the command type) with iden-tifier identifier
                  tifier id.  Addr is a pointer to a struct dqblk structure.  The usage fields of the dqblk
                  structure are ignored.  This call is restricted to the super-user.

     Q_SETUSE     Set disk usage limits for the user or group (as determined by the command type) with iden-tifier identifier
                  tifier id.  Addr is a pointer to a struct dqblk structure.  Only the usage fields are
                  used.  This call is restricted to the super-user.

     Q_SYNC       Update the on-disk copy of quota usages.  The command type specifies which type of quotas
                  are to be updated.  The id and addr parameters are ignored.

     Q_QUOTASTAT  Get the enable status for the filesystem specified by path.  The command type specifies
                  the type of the quotas whose status is being queried.  Addr is a pointer to an integer.
                  Upon return, this integer will hold a zero value if quotas for the given type are not
                  enabled and a non-zero value if quotas for the given type are enabled.  The id parameter
                  is ignored.

RETURN VALUES
     A successful call returns 0, otherwise the value -1 is returned and the global variable errno indicates
     the reason for the failure.

ERRORS
     A quotactl() call will fail if:

     [ENOTSUP]          The kernel has not been compiled with the QUOTA option.

     [EUSERS]           The quota table cannot be expanded.

     [EINVAL]           Cmd or the command type is invalid.

     [EACCES]           In Q_QUOTAON, the quota file is not a plain file.

     [EACCES]           Search permission is denied for a component of a path prefix.

     [ENOTDIR]          A component of a path prefix was not a directory.

     [ENAMETOOLONG]     A component of a pathname exceeded {NAME_MAX} characters, or an entire path name
                        exceeded {PATH_MAX} characters.

     [ENOENT]           A filename does not exist.

     [ELOOP]            Too many symbolic links were encountered in translating a pathname.

     [EROFS]            In Q_QUOTAON, the quota file resides on a read-only filesystem.

     [EIO]              An I/O error occurred while reading from or writing to a file containing quotas.

     [EFAULT]           An invalid addr was supplied; the associated structure could not be copied in or out
                        of the kernel.

     [EFAULT]           Path points outside the process's allocated address space.

     [EPERM]            The call was privileged and the caller was not the super-user.

SEE ALSO
     quota(1), fstab(5), edquota(8), quotacheck(8), quotaon(8), repquota(8)

BUGS
     There should be some way to integrate this call with the resource limit interface provided by
     setrlimit(2) and getrlimit(2).

HISTORY
     The quotactl() function call appeared in 4.3BSD-Reno.

BSD                              June 4, 1993                              BSD