int setvbuf( FILE *stream, char *buf, int type, size_t size )

	- prototype in stdio.h

	- causes buf to be used for I/O buffering instead of the auto-
	  matically allocated buffer; used after given stream is opened
	  and before output
	- in setvbuf, if buf is NULL, a buffer is allocated via malloc()
	- no I/O to the file should occur until after buffering is set

	- see	setbuf()