[microproject idea]

Find places where we scan a string twice unnecessarily, once with
strchr() and then with strlen(), e.g.

	const char *colon = strchr(name, ':');
	int namelen = colon ? colon - name : strlen(name);

and rewrite such a pattern using strchrnul() as appropriate.

The above example can become

	const char *colon = strchrnul(name, ':');
        int namelen = colon - name;