Re: How to exit if program is not found

[Timothy Madden]

On 06/14/2012 07:07 PM, Roger Pau Monné wrote:
> On Thu, Jun 14, 2012 at 5:01 PM, Timothy Madden<address@hidden>  wrote:
> > Hello
> >
> > I see in the info pages that autoconf macros check for various programs and
> > set a variable if found, but how do I get the behaviour I see in most
> > configure programs to exit with an error if a program is not found ?
>
> I usually use the following macro:
>
> AC_DEFUN([AX_PATH_PROG_OR_FAIL],
> [AC_PATH_PROG([$1], [$2], [no])
> if test x"${$1}" == x"no"
> then
>      AC_MSG_ERROR([Unable to find $2, please install $2])
> fi])
>
> So on my configure.ac I make the following calls:
>
> AX_PATH_PROG_OR_FAIL([PERL], [perl])
>
> Where "PERL" is the name of the variable where to store the path, and
> "perl" is the name of the program to search for.

How about the predefined programs ?

AC_PROG_YACC might set YACC to 'bison -y', how would I check that 'bison 
-y' is found or is on path ?

And really, is there no support in autoconf itself for this ?

Thank you,
Timothy Madden