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32 .\" @(#)fsync.2 8.1 (Berkeley) 6/4/93
40 .Nd "synchronize a file's in-core state with that on disk"
42 .Fd #include <unistd.h>
47 causes all modified data and attributes of
49 to be moved to a permanent storage device.
50 This normally results in all in-core modified copies
51 of buffers for the associated file to be written to a disk.
54 should be used by programs that require a file to be
55 in a known state, for example, in building a simple transaction
57 .Sh IMPLEMENTATION NOTES
59 In the non-threaded library
65 In the threaded library, the
67 syscall is assembled to
71 is implemented as a function which locks
73 for read and write, then calls
74 .Fn _thread_sys_fsync .
80 A 0 value is returned on success. A -1 value indicates
89 is not a valid descriptor.
92 refers to a socket, not to a file.
94 An I/O error occurred while reading from or writing to the file system.
103 function call appeared in