Various additions and fixes.

src/lib9/getuser.c

@@ -0,0 +1,17 @@
+#include <pwd.h>
+
+#include <u.h>
+#include <libc.h>
+
+char*
+getuser(void)
+{
+	static char user[64];
+	struct passwd *pw;
+
+	pw = getpwuid(getuid());
+	if(pw == nil)
+		return "none";
+	strecpy(user, user+sizeof user, pw->pw_name);
+	return user;
+}