[rrdtool-maint] hurd-i386 issue with sigwaitinfo

[Samuel Thibault]

Hello,

As I expected, sigwaitinfo is not implemented, and the symbol you get is
the glibc stub.  This is howver announced in
/usr/include/i386-gnu/gnu/stubs.h:

#define __stub_sigwaitinfo

and detected by autoconf, see config.log:

| #if defined __stub_sigwaitinfo || defined __stub___sigwaitinfo
| choke me
| #endif

but that's only when using AC_CHECK_FUNCS.  When using AC_CHECK_LIB, it
doesn't do this kind of check.  In a way, that's normal: AC_CHECK_LIB
is made to check for the presence of a lib, not for the presence of a
symbol (and actually sigwaitinfo is not even in librt...).  Ideally
the AC_CHECK_FUNCS macro should still be used, with a modified LIBS.

Samuel