NAME    [Toc]    [Back]

     fsync - synchronize a file's in-core state with that on disk

LIBRARY    [Toc]    [Back]

     Standard C Library (libc, -lc)

SYNOPSIS    [Toc]    [Back]

     #include <unistd.h>

     int
     fsync(int fd);

DESCRIPTION    [Toc]    [Back]

     fsync() causes all modified data and attributes of fd to be moved to a
     permanent storage device.  This normally results in all in-core modified
     copies of buffers for the associated file to be written to a disk.

     fsync() should be used by programs that require a file to be in a known
     state, for example, in building a simple transaction facility.

RETURN VALUES    [Toc]    [Back]

     A 0 value is returned on success.  A -1 value indicates an error.

ERRORS    [Toc]    [Back]

     The fsync() fails if:

     [EBADF]            fd is not a valid descriptor.

     [EINVAL]           fd refers to a socket, not to a file.

     [EIO]              An I/O error occurred while reading from or writing to
                        the file system.

SEE ALSO    [Toc]    [Back]

     sync(2), sync(8)

HISTORY    [Toc]    [Back]

     The fsync() function call appeared in 4.2BSD.

BSD                              June 4, 1993                              BSD