/* write a hex dump expansion of *p1... to fp
   p1: the source
   fp: output stream to write to */
static void listto(char *p1, FILE *fp)
{
	p1--;
	for (; *p1++; /* p1<spend */ )		/* no effect ? */
		if (isprint(*p1))
			putc(*p1, fp);		/* pass it through */
		else
		{
			putc('\\', fp);		/* emit a backslash */
			switch(*p1)
			{
			case '\b':	putc('b', fp); break;	/* BS */
			case '\t':	putc('t', fp); break;	/* TAB */
			case '\n':	putc('n', fp); break;	/* NL */
			case '\r':	putc('r', fp); break;	/* CR */
			case '\033':	putc('e', fp); break;	/* ESC */
			default:	fprintf(fp, "%02x", *p1 & 0xFF);
			}
		}
	putc('\n', fp);
}