AC_PROG_MKDIR_P documentation

[Stepan Kasal]

Hello,
  the documentation says:

+[...] Also, @code{AS_MKDIR_P} does not accept options,
+but if you are willing to assume Posix 1003.2-1992 or later, a
address@hidden can use the @option{-m} option,

That sounds weird, considering the fact that MKDIR_P refers either to
GNU mkdir or to the install-sh script delivered together with the
package.

Option -m is not handled if the system contains a version of GNU mkdir
which doesn't have it.  (Haven't checked the history of fileutils.)

The documentation also says:
+[..] The program is checked to make
+sure that it is thread-safe (@pxref{Limitations of Usual Tools}).

Ouch!  We do not check anything, we just _know_ that if install-sh is
current, it is probably thread-safe.  (The most ugly race condition
was removed, and we don't know about other problem.)

And are we really sure that ancient versions of GNU mkdir were thread
safe?

I suggest to simply say

... but you can use @code{MKDIR_P} with the @option{-m} option, ...

and

... On recent system, the program is thread-safe.

Well, I have probably missed something.

Have a nice day,
        Stepan