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─────Run-Time Library───────────────────────────────────────────────────────
 
  Constant:  "c", "n"
 
  Include:   <stdio.h>
 
  Context:   _fdopen, fopen
 
  Summary:   Specifies whether the buffer associated with the open
             file is flushed to the operating system's buffers or to
             disk. The mode is included in the string specifying the
             type of access ("r", "w", "a", "r+", "w+", "a+").
 
     The modes are described below.
 
     Mode     Meaning
 
     "c"      Write the unwritten contents of the specified buffer to
              disk. This commit-to-disk functionality only occurs at
              explicit calls to either the fflush or the _flushall
              function. This mode is useful when dealing with sensitive
              data. For example, if your program dies after a call to
              fflush or _flushall, you can be sure that your data
              reached the operating system's buffers. However, unless a
              file is opened with the "c" option, the data might never
              make it to disk if the operating system also dies.
 
     "n"      Write the unwritten contents of the specified buffer to
              the operating system's buffers. The operating system can
              cache data and then determine an optimal time to write
              to disk. Under many conditions, this behavior makes for
              efficient program behavior. However, if the retention of
              data is critical (such as bank transactions or airline
              ticket information) consider using the "c" option. The
              "n" mode is the default.
 
     NOTE: The "c" and "n" options are not part of the ANSI standard
           for fopen, but are Microsoft extensions and should not be
           used where ANSI portability is desired.
 
     See: ◄COMMODE.OBJ►
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