@node sync, unix
@subheading Syntax

@example
#include <unistd.h>

int sync(void);
@end example

@subheading Description

Intended to assist porting Unix programs.  Under Unix, @code{sync}
flushes all caches of previously written data.  In this implementation,
@code{sync} calls @code{fsync} on every open file.  @xref{fsync}.  It
also calls @code{_flush_disk_cache} (@pxref{_flush_disk_cache}) to try
to force cached data to the disk.

@subheading Return Value

Always returns 0.

@subheading Portability

@portability !ansi, !posix

@subheading Example

@example
sync();
@end example