1 files changed, 48 insertions, 0 deletions
diff --git a/appl/cmd/cd.b b/appl/cmd/cd.b
new file mode 100644
index 00000000..57c94aba
--- /dev/null
+++ b/appl/cmd/cd.b
@@ -0,0 +1,48 @@
+implement Cd;
+
+include "sys.m";
+	sys: Sys;
+
+include "draw.m";
+
+Cd: module
+{
+	init:	fn(ctxt: ref Draw->Context, argv: list of string);
+};
+
+stderr: ref Sys->FD;
+
+init(nil: ref Draw->Context, argv: list of string)
+{
+	sys = load Sys Sys->PATH;
+
+	stderr = sys->fildes(2);
+
+	argv = tl argv;
+	if(argv == nil)
+		argv = "/usr/"+user() :: nil;
+
+	if(tl argv != nil) {
+		sys->fprint(stderr, "Usage: cd [directory]\n");
+		raise "fail:usage";
+	}
+
+	if(sys->chdir(hd argv) < 0) {
+		sys->fprint(stderr, "cd: %s: %r\n", hd argv);
+		raise "fail:failed";
+	}
+}
+
+user(): string
+{
+	fd := sys->open("/dev/user", sys->OREAD);
+	if(fd == nil)
+		return "inferno";
+
+	buf := array[Sys->NAMEMAX] of byte;
+	n := sys->read(fd, buf, len buf);
+	if(n <= 0)
+		return "inferno";
+
+	return string buf[0:n];
+}