FSYNC(2)                             SysV                             FSYNC(2)



NAME
     fsync - Writes changes in a file to permanent storage

SYNOPSIS
     int fsync (filedes )
     int filedes;

DESCRIPTION
     The fsync function saves all modified data in the file open on the
     filedes argument to permanent storage. filedes Specifies a valid open
     file descriptor.

     On return from the fsync function, all updates have been saved on
     permanent storage.

DIAGNOSTICS
     Upon successful completion, the fsync function returns a value of 0
     (zero). If fsync fails, a value of -1 is returned and errno is set to
     indicate the error.

ERRORS
     fsync function fails if:

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

     [EBADF]   The filedes argument is not a valid file descriptor open for
               writing.

     [EINVAL]  The filedes argument does not refer to a file on which this
               operation is possible.

     [EINTR]   The fsync function was interrupted by a signal which was
               caught.

SEE ALSO
     open(2), sync(2), write(2)