Re: [9fans] tcs bug.

[Russ Cox <rsc@swtch.com>]

You've invented buffered I/O.

#include <u.h>
#include <libc.h>
#include <bio.h>

void
usage(void)
{
	fprint(2, "usage: runecvt [-l | -t | -u] [file...]\n");
	exits("usage");
}

void
convert(Biobuf *bin, Biobuf *bout, Rune (*fn)(Rune))
{
	int c;
	
	while((c = Bgetrune(bin)) != -1)
		Bputrune(bout, fn(c));
}

void
main(int argc, char **argv)
{
	int i;
	Biobuf *b, bin, bout;
	Rune (*fn)(Rune);
	
	fn = toupperrune;
	ARGBEGIN{
	case 'l':
		fn = tolowerrune;
		break;
	case 't':
		fn = totitlerune;
		break;
	case 'u':
		fn = toupperrune;
		break;
	default:
		usage();
	}ARGEND
	
	Binit(&bout, 1, OWRITE);
	if(argc == 0){
		Binit(&bin, 0, OREAD);
		convert(&bin, &bout, fn);
	}else{
		for(i=0; i<argc; i++){
			if((b = Bopen(argv[i], OREAD)) == nil)
				sysfatal("open %s: %r", argv[i]);
			convert(b, &bout, fn);
		}
	}
	Bterm(&bout);
	exits(nil);
}