.\" Copyright 1996, Andries E. Brouwer <aeb@cwi.nl>
.\" Copyright 2010, Jan Kara <jack@suse.cz>
.\" Copyright 2010, Michael Kerrisk <mtk.manpages@gmail.com>
.\" Copyright, the authors of the Linux man-pages project
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
.TH Q_SYNC 2const 2026-06-05 "Linux man-pages 6.19"
.SH NAME
Q_SYNC
\-
synchronize on-disk copy of quota usages
.SH LIBRARY
Standard C library
.RI ( libc ,\~ \-lc )
.SH SYNOPSIS
.nf
.B #include <sys/quota.h>
.P
.BI "int\~quotactl(QCMD(Q_SYNC, " type "), const\~char\~*_Nullable\~" special ", 0, NULL);"
.P
.BR "#include <sys/quota.h>" "    /* Definition of " Q_* " constants */"
.BR "#include <sys/syscall.h>" "  /* Definition of " SYS_* " constants */"
.B #include <unistd.h>
.P
.BI "int\~syscall(SYS_quotactl_fd, int\~" fd ", QCMD(Q_SYNC, " type "));"
.fi
.SH DESCRIPTION
Update the on-disk copy of quota usages for a filesystem.
.P
For
.BR quotactl (2),
if
.I special
is NULL, then all filesystems with active quotas are synchronized.
.BR quotactl_fd (2)
always synchronizes only one filesystem.
.SH RETURN VALUE
See
.BR quotactl (2).
.SH ERRORS
See
.BR quotactl (2).
.SH STANDARDS
Linux.
.SH HISTORY
Linux.
.SH SEE ALSO
.BR quotactl (2),
.BR quotactl_fd (2)