TC: int _creat( const char *fname, int attr )

	- prototype in io.h, also include dos.h

	- creates new file (overwrites existing file) of filename with file
	  attribute attr, for both read/write
	- attr can be a combination of the following

	  FA_RDONLY   set read only attribute
	  FA_HIDDEN   set hidden attribute
	  FA_SYSTEM   set system attribute

	- file is created in O_BINARY mode
	- returns nonnegative integer if OK, else -1
	- uses DOS function INT 21,3C
	- MSC uses _dos_creat()