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[[!meta title="fsys_syncfs"]]

    routine fsys_syncfs (
    	fsys: fsys_t;
    	RPT
    	wait: int;
    	do_children: int);

Synchronize the entire filesystem.

This function has a companion in [[`file_syncfs`|file_syncfs]], which is
invoked on an arbitrary node instead of the server's control port.  Both of
them are usually implemented in equivalent ways.

# Implementation Examples

Servers that either don't keep any unsynchronized state (or don't have a
backing store at all) can simply `return 0`.  Examples: [[translator/symlink]],
[[translator/nfs]].

## [[libtrivfs]]

Invoke [[`file_sync`|file_sync]] on the underlying node.  Rationale: the
underlying node represents this filesystem's backend, and once this node is
synchronized, the whole [[libtrivfs]]-based filesystem is to be considered
synchronized.

### [[storeio]] / [[streamio]]

Instead of to the underlying node, pass the call through to the backend
(device).

## [[libnetfs]]

Invoke `netfs_attempt_syncfs`.

## [[libdiskfs]]

Invoke [[`fsys_syncfs`|fsys_syncfs]] on all active children, and invoke
`diskfs_sync_everything` and `diskfs_set_hypermetadata`.

# Usage Examples

## [[libdiskfs]]

In the implementations of both [[`file_syncfs`|file_syncfs]] and
[[`fsys_syncfs`|fsys_syncfs]], [[`fsys_syncfs`|fsys_syncfs]] is invoked on all
active children.