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SYNC

Section: Linux Programmer's Manual (2)
Updated: 2001-10-10
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NAME

sync - commit buffer cache to disk  

SYNOPSIS

#include <unistd.h>

void sync(void);  

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)


 

Index

NAME
SYNOPSIS
DESCRIPTION
ERRORS
CONFORMING TO
NOTES
BUGS
SEE ALSO