Loooking for a non-standard include file.

[David Kirkby]

Hi,
        I am writing a programme that needs to use header file used by the GNU
Scientific Library (gsl). By default, gsl installs its header files in
/$PREFIX/include/gsl (usually /usr/local/include/gsl).

The programmes that use the gsl library, should, according to their convention,
start like this:
#include <gsl/header1.h>
#include <gsl/header2.h>

Obviously, this only works if /usr/local/include is included in the search path
for the compiler. 

How can I force autoconf to look for the include files in these locations ? My
current autoconf.in is shown below, but this is not finding the header file
gsl/gsl_sf_expint.h. 

Any suggestions ??? 

@dnl Process this file with autoconf to produce a configure script.
AC_INIT(src/yagi.c)
AM_INIT_AUTOMAKE(yagi-uda, 2.0)

dnl Checks for programs.
AC_PROG_CC
AC_ISC_POSIX

AC_OUTPUT_COMMANDS([exit])

dnl Checks for libraries.
AC_CHECK_LIB(m,log)
AC_CHECK_LIB(m,main)
AC_CHECK_LIB(gslcblas,main)
AC_CHECK_LIB(gsl,main)
AC_CHECK_LIB(gsl,gsl_sf_Si, ,echo "You MUST install a recent version of the GNU
Maths L
ibrary (gsl)"
echo "available from http://www.gnu.org/software/gsl/gsl.html";
exit 1)

dnl Checks for header files.
AC_STDC_HEADERS
AC_HAVE_HEADERS(gsl/gsl_sf_expint.h)


dnl Check for st_blksize in struct stat
AC_ST_BLKSIZE

AC_OUTPUT([Makefile src/Makefile  man/Makefile])

-- 
Dr. David Kirkby Ph.D,
email: address@hidden 
former email address: address@hidden
web page: http://www.david-kirkby.co.uk/
Amateur radio callsign: G8WRB