FILE *fopen( const char *filename, const char *type )

	- prototype in stdio.h

	- type is a combination of the following:
		Mode	   Description
		"r"	read text/binary
		"w"	write text/binary
		"a"	append text/binary
		"+"	allow update access
		"t"	text file
		"b"	binary file

		Read	Write	Append
		"rt"	"wt"	"at"	(text)
		"rb"	"wb"	"ab"	(binary)
		"r+"	"w+"	"a+"	(update)
		"r+t"	"w+t"	"a+t"	(update text)
		"r+b"	"w+b"	"a+b"	(update binary)

	read   - read only (unless "r+")
	write  - create
	append - seek to end of file or create file

	- text mode input, will have CRs discarded
	- using any of the stdio functions results in a default allocation
	  of 512 bytes for the I/O buffer and the inclusion of the standard
	  memory allocation functions
	- returns stream or NULL on error