set prompt-escape-character

[Andrew Cagney]

More -Wformat-nonliteral suprizes.  In trying to understand the "top.c" 
warnings from:

      /* FIXME: how to protect GDB from crashing
         from bad user-supplied format string? */
      sprintf (outp, fmt[0] == 0 ? default_fmt : fmt,
               tmp);

I discovered a new feature:

(top-gdb) set prompt-escape-char 0x25
(top-gdb) set prompt PC=0x%0x%$pc
PC=0x1802f68

Perhaps it could be change do use the printf code vis:
	set prompt "0x%x ", $pc

Anyway, Michael, was there any doco on this?  I can't find anything.

Andrew