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$FreeBSD: projects/quota64/lib/libutil/quotafile.3 188604 2009-02-14 08:08:08Z mckusick $
.Dd February 14, 2009 .Dt QUOTAFILE 3 .Os .Sh NAME .Nm quota_open .Nm quota_read .Nm quota_write_limits .Nm quota_write_usage .Nm quota_close .Nd "Manipulate quotas" .Sh LIBRARY .Lb libutil .Sh SYNOPSIS n ufs/ufs/quota.h n libutil.h n fstab.h .Ft "struct quotafile *" .Fn quota_open "struct fstab *fs" "int quotatype" "int openflags" .Ft int .Fn quota_read "struct quotafile *qf" "struct dqblk *dqb" "int id" .Ft int .Fn quota_write_limits "struct quotafile *qf" "struct dqblk *dqb" "int id" .Ft int .Fn quota_write_usage "struct quotafile *qf" "struct dqblk *dqb" "int id" .Ft int .Fn quota_close "struct quotafile *qf" .Sh DESCRIPTION These functions are designed to simplify access to filesystem quotas. If quotas are active on a filesystem, these functions will access them directly from the kernel using the .Fn quotactl system call. If quotas are not active, these functions will access them by reading and writing the quota files directly.
p The .Fn quota_open function takes a pointer to an .Vt fstab entry corresponding to the filesystem on which quotas are to be accessed. The .Va quotatype field indicates the type of quotas being sought, either .Dv USRQUOTA or .Dv GRPQUOTA . The .Va openflags are those used by the .Fn open system call, usually either .Dv O_RDONLY if the quotas are just to be read, or .Dv O_RDWR if the quotas are to be updated. The .Dv O_CREAT flag should be specified if a new quota file of the requested type should be created if it does not already exist.
p The .Fn quota_read function reads the quota from the filesystem and quota type referenced by .Va qf for the user (or group) specified by .Va id into the .Vt dqblk quota structure pointed to by .Va dqb .
p The .Fn quota_write_limits function updates the limit fields (but not the usage fields) for the filesystem and quota type referenced by .Va qf for the user (or group) specified by .Va id from the .Vt dqblk quota structure pointed to by .Va dqb .
p The .Fn quota_write_usage function updates the usage fields (but not the limit fields) for the filesystem and quota type referenced by .Va qf for the user (or group) specified by .Va id from the .Vt dqblk quota structure pointed to by .Va dqb .
p The .Fn quota_close function closes any open file descriptors and frees any storage associated with the filesystem and quota type referenced by .Va qf . .Sh RETURN VALUES If the filesystem has quotas associated with it, .Fn quota_open returns a pointer to a .Vt quotafile structure used in subsequent quota access calls. If the filesystem has no quotas, or access permission is denied .Dv NULL is returned and .Va errno is set to indicate the cause of failure.
p The .Fn quota_read , .Fn quota_write_limits , .Fn quota_write_usage , and .Fn quota_close functions return zero on success. On error they return .Dv -1 and set .Va errno to indicate the cause of failure. .Sh SEE ALSO .Xr quotactl 2 , .Xr quota.user 5 , .Xr quota.group 5 .Sh HISTORY The .Nm functions first appeared in .Fx 8.0 . .Sh AUTHORS .An -nosplit The .Nm functions and this manual page were written by .An Dag-Erling Sm\(/orgrav Aq des@FreeBSD.org and .An Marshall Kirk McKusick .