//-------------------------------------------------------------------
//	out2file.cpp
//
//	This program uses a high-level programming language to show
//	how an application can use standard UNIX library-functions,
//	such as open(), write(), and close(), to create a textfile.  
//
//	We ultimately want to see how to write such a program using
//	low-level assembly language, but often it is useful to have
//	a working solution first in a high-level language (so we're
//	sure we've identified all of the elements that are needed).   
//
//	       compile using:  $ g++ out2file.cpp -o out2file
//	       execute using:  $ ./out2file
//	       confirm using:  $ cat ./mycookie.dat
//
//	programmer: ALLAN CRUSE
//	written on: 23 JAN 2008
//-------------------------------------------------------------------

#include <stdio.h>	// for printf(), perror() 
#include <fcntl.h>	// for open(), O_WRONLY, etc. 
#include <stdlib.h>	// for exit() 
#include <unistd.h>	// for write(), close() 

char	filename[] = "mycookie.dat";
char	filedata[] = "Computer Science 210\nSpring 2008\n";
int	len = sizeof( filedata ) - 1;

int main( int argc, char **argv )
{
	// open a new file for writing
	int	fd = open( filename, O_WRONLY | O_CREAT | O_TRUNC, 0644 );
	if ( fd < 0 ) { perror( "open" ); exit(1); }
	
	// write out data to the file
	int	nbytes = write( fd, filedata, len );
	if ( nbytes < 0 ) { perror( "write" ); exit(1); }

	// close the file (needed to 'commit' the file's data to storage)
	close( fd );
}