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─────Run-Time Library───────────────────────────────────────────────────────
 
     The _creat function either creates a new file or opens and
     truncates an existing file. If the file specified by <filename>
     does not exist, a new file is created with the given permission
     setting and is opened for writing. If the file already exists and
     its permission setting allows writing, _creat truncates the file
     to length 0, destroying the previous contents, and opens it for
     writing.
 
     The permission setting, <pmode>, applies to newly created files
     only. The new file receives the specified permission setting after
     it is closed for the first time. The integer expression <pmode>
     contains one or both of the manifest constants _S_IWRITE and
     _S_IREAD, defined in SYS\STAT.H. When both constants are given,
     they are joined with the bitwise-OR operator (|). The meaning of
     the <pmode> argument is determined by the _S_IWRITE or _S_IREAD
     manifest constant.
 
     If write permission is not given, the file is read-only. Note that
     all files are always readable; it is not possible to give write-
     only permission. Thus, modes _S_IWRITE and _S_IREAD | _S_IWRITE
     are equivalent. Under DOS versions 3.0 and later, files opened
     using _creat are always opened in compatibility mode (see _sopen).
     With DOS32X, the files are always opened with _SH_DENYNO.
 
     The _creat function applies the current file-permission mask to
     <pmode> before setting the permissions (see _umask).
 
     Note that the _creat routine is provided primarily for
     compatibility with previous libraries. A call to _open with
     _O_CREAT and _O_TRUNC in the <oflag> argument is equivalent to
     _creat and is preferable for new code.
 
     Return Value
 
     If successful, _creat returns a handle for the created file.
     Otherwise, it returns -1 and sets errno to EACCES, EMFILE, or
     ENOENT.
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