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sync(2) [sunos man page]

sync(2) 							   System Calls 							   sync(2)

NAME
sync - update super block SYNOPSIS
#include <unistd.h> void sync(void); DESCRIPTION
The sync() function writes all information in memory that should be on disk, including modified super blocks, modified inodes, and delayed block I/O. Unlike fsync(3C), which completes the writing before it returns, sync() schedules but does not necessarily complete the writing before returning. USAGE
The sync() function should be used by applications that examine a file system, such as fsck(1M), and df(1M), and is mandatory before rebooting. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
df(1M), fsck(1M), fsync(3C), attributes(5), standards(5) SunOS 5.10 5 Jul 1990 sync(2)

Check Out this Related Man Page

SYNC(2) 						     Linux Programmer's Manual							   SYNC(2)

NAME
sync - commit buffer cache to disk SYNOPSIS
#include <unistd.h> void sync(void); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): sync(): _BSD_SOURCE || _XOPEN_SOURCE >= 500 || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED DESCRIPTION
sync() first commits inodes to buffers, and then buffers to disk. ERRORS
This function is always successful. CONFORMING TO
SVr4, 4.3BSD, POSIX.1-2001. NOTES
Since glibc 2.2.2 the Linux prototype is as listed above, following the various standards. In libc4, libc5, and glibc up to 2.2.1 it was "int sync(void)", and sync() always returned 0. BUGS
According to the standard specification (e.g., POSIX.1-2001), sync() schedules the writes, but may return before the actual writing is done. However, since version 1.3.20 Linux does actually wait. (This still does not guarantee data integrity: modern disks have large caches.) SEE ALSO
bdflush(2), fdatasync(2), fsync(2), sync(8), update(8) COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 2010-09-20 SYNC(2)

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