Copyright (c) 1983, 1990, 1991, 1993 The Regents of the University of California. All rights reserved. This code is derived from software contributed to Berkeley by Robert Elz at The University of Melbourne. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2....
NAMEquotactl - manipulate file system quotas
SYNOPSISIn sys/types.h In ufs/ufs/quota.h Ft int Fn quotactl const char *path int cmd int id void *addr
DESCRIPTIONThe Fn quotactl system call enables, disables and manipulates file system quotas. A quota control command given by Fa cmd operates on the given filename Fa path for the given user or group Fa id . (NOTE: One should use the QCMD macro defined in In ufs/ufs/quota.h to formulate the value for Fa cmd . ) The address of an optional command specific data structure, Fa addr , may be given; its interpretation is discussed below with each command.
For commands that use the Fa id identifier, it must be either -1 or any positive value. The value of -1 indicates that the current UID or GID should be used. Any other negative value will return an error.
Currently quotas are supported only for the ``ufs'' file system. For ``ufs'' a command is composed of a primary command (see below) and a command type used to interpret the Fa id . Types are supported for interpretation of user identifiers (USRQUOTA) and group identifiers (GRPQUOTA). The ``ufs'' specific commands are:
- Enable disk quotas for the file system specified by Fa path . The command type specifies the type of the quotas being enabled. The Fa addr argument specifies a file from which to take the quotas. The quota file must exist; it is normally created with the quotacheck(8) program. The Fa id argument is unused. Only the super-user may turn quotas on.
- Disable disk quotas for the file system specified by Fa path . The command type specifies the type of the quotas being disabled. The Fa addr and Fa id arguments are unused. Only the super-user may turn quotas off.
- Get the wordsize used to represent the quotas for the user or group (as determined by the command type). Possible values are 32 for the old-style quota file and 64 for the new-style quota file. The Fa addr argument is a pointer to an integer into which the size is stored. The identifier Fa id is not used.
- Get disk quota limits and current usage for the user or group (as determined by the command type) with identifier Fa id . The Fa addr argument is a pointer to a Fa struct dqblk structure (defined in In ufs/ufs/quota.h ) .
- Set disk quota limits for the user or group (as determined by the command type) with identifier Fa id . The Fa addr argument is a pointer to a Fa struct dqblk structure (defined in In ufs/ufs/quota.h ) . The usage fields of the Fa dqblk structure are ignored. This system call is restricted to the super-user.
- Set disk usage limits for the user or group (as determined by the command type) with identifier Fa id . The Fa addr argument is a pointer to a Fa struct dqblk structure (defined in In ufs/ufs/quota.h ) . Only the usage fields are used. This system call is restricted to the super-user.
- Update the on-disk copy of quota usages. The command type specifies which type of quotas are to be updated. The Fa id and Fa addr arguments are ignored.
RETURN VALUESRv -std quotactl
ERRORSThe Fn quotactl system call will fail if:
- Bq Er EOPNOTSUPP
- The kernel has not been compiled with the QUOTA option.
- Bq Er EUSERS
- The quota table cannot be expanded.
- Bq Er EINVAL
or the command type is invalid.
quotas are not currently enabled for this file system.
The Fa id argument to Q_GETQUOTA Q_SETQUOTA or Q_SETUSE is a negative value.
- Bq Er EACCES
- In Q_QUOTAON the quota file is not a plain file.
- Bq Er EACCES
- Search permission is denied for a component of a path prefix.
- Bq Er ENOTDIR
- A component of a path prefix was not a directory.
- Bq Er ENAMETOOLONG
- A component of either pathname exceeded 255 characters, or the entire length of either path name exceeded 1023 characters.
- Bq Er ENOENT
- A filename does not exist.
- Bq Er ELOOP
- Too many symbolic links were encountered in translating a pathname.
- Bq Er EROFS
- In Q_QUOTAON either the file system on which quotas are to be enabled is mounted read-only or the quota file resides on a read-only file system.
- Bq Er EIO
- An I/O error occurred while reading from or writing to a file containing quotas.
- Bq Er EFAULT
- An invalid Fa addr was supplied; the associated structure could not be copied in or out of the kernel.
- Bq Er EFAULT
- The Fa path argument points outside the process's allocated address space.
- Bq Er EPERM
- The call was privileged and the caller was not the super-user.