On Thu, 2005-10-27 at 08:29 +0800, Steven Woody wrote: > Ralf Corsepius <[EMAIL PROTECTED]> writes: > > > On Wed, 2005-10-26 at 21:52 +0800, Steven Woody wrote: > >> Stepan Kasal <[EMAIL PROTECTED]> writes: > >> > >> > Hello, > >> > > >> > On Tue, Oct 25, 2005 at 10:23:55PM +0800, Steven Woody wrote: > >> >> #ifdef HAVE_LIMITS > >> > > >> > add line > >> > > >> > AC_CHECK_HEADERS([limits]) > >> > > >> > to configure.ac (or configure.in). > >> > > >> > HTH, > >> > Stepan Kasal > >> > >> thanks. but still got problem. if i say, AC_CHECK_HEADERS([limits]) as you > >> pointed, the the configure script will complain and the HAVE_LIMITS > >> veriable > >> would't be set because my system (Linux) only get limits.h instead of > >> 'limits'. > >> > >> so to make 'configure' happy, i changed to AC_CHECK_HEADERS([limits.h]), > >> this > >> time, 'configure' feels happy and HAVE_LIMITS_H is set properly. but the > >> third-party headers used in my project requires a HAVE_LIMITS that is > >> still not > >> set. > >> > >> my current solution is add the below line into 'config.h.in': > >> > >> #define HAVE_LIMITS 1 > >> > >> but i think this is not a decent way. any thinking? > > > > You seem to be confused and are outsmarting yourself ;) > > > > limits.h is a POSIX header. On linux it is supplied by GCC. > > > > So if you want to check for "limits", you should use > > AC_CHECK_HEADERS([limits]) > > > > but could you explain why AC_CHECK_HEADERS([limits]) failed but > AC_CHECK_HEADERS([limits.h]) success? AC_CHECK_HEADER by default uses the c-compiler.
To check for C++-headers you normally have to tell the configure script to switch languages/compilers. Example: # This uses the c-compiler AC_CHECK_HEADERS([limits.h]) # This uses the c++-compiler AC_LANG_PUSH([C++]) AC_CHECK_HEADERS([limits]) AC_LANG_POP Ralf
