GNU Autotools-如何处理必需但可能缺少的标题？

Question

I was wondering about the best-practice solution of handling required headers with GNU Autotools. This is one line from my configure.ac

AC_CHECK_HEADERS_ONCE(argp.h)

If the argp.h is missing on a system, then configure will just proclaim

...
checking for argp.h... no
...

but do nothing about it. Of course, the program will fail to compile, because the expected header does not exist, and wrapping the include in #ifdef HAVE_ARGP_H directives, and possibly adding an #else #error [...] construct would do what I want, but it seems rather tedious.

Is there a good way to error out on missing but required headers on configure time as opposed to compile time?

Thanks, Andy

Answer 1

Replace your AC_CHECK_HEADERS_ONCE call with:

AC_CHECK_HEADER([argp.h], [], AC_MSG_ERROR([cannot find required header argp.h]))

This variant won't define HAVE_ARGP_H , but you don't need that anyway since your code requires that header unconditionally. The error stops the configure process.