fsync(2) [opendarwin man page]

FSYNC(2)						      BSD System Calls Manual							  FSYNC(2)

NAME

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

SYNOPSIS

     #include <unistd.h>

     int
     fsync(int fd);

DESCRIPTION

     Fsync() causes all modified data and attributes of fd to be moved to a permanent storage device.  This normally results in all in-core modi-
     fied 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

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

ERRORS

     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

     sync(2), sync(8), update(8)

HISTORY

     The fsync() function call appeared in 4.2BSD.

4.2 Berkeley Distribution					   June 4, 1993 					 4.2 Berkeley Distribution

FSYNC(2)						      BSD System Calls Manual							  FSYNC(2)

NAME

     fsync -- synchronise changes to a file

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <unistd.h>

     int
     fsync(int fd);

DESCRIPTION

     The fsync() system call 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.

     The fsync() system call 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

     The fsync() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate
     the error.

ERRORS

     The fsync() fails if:

     [EBADF]		The fd argument is not a valid descriptor.

     [EINVAL]		The fd argument 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

     sync(2), syncer(4), sync(8)

HISTORY

     The fsync() system call appeared in 4.2BSD.

BSD
								   June 4, 1993 							       BSD