For applications using autoconf the standard macro
AC_CHECK_LIB can be used to link with the library automatically
from a configure script. The library itself depends on the
presence of a CBLAS and math library as well, so these must also be
located before linking with the main libgsl file. The following
commands should be placed in the `configure.in' file to perform
these tests,
AC_CHECK_LIB(m,main) AC_CHECK_LIB(gslcblas,main) AC_CHECK_LIB(gsl,main)
Assuming the libraries are found the output during the configure stage looks like this,
checking for main in -lm... yes checking for main in -lgslcblas... yes checking for main in -lgsl... yes
If the library is found then the tests will define the macros
HAVE_LIBGSL, HAVE_LIBGSLCBLAS, HAVE_LIBM and add
the options -lgsl -lgslcblas -lm to the variable LIBS.
The tests above will find any version of the library. They are suitable for general use, where the versions of the functions are not important. An alternative macro is available in the file `gsl.m4' to test for a specific version of the library. To use this macro simply add the following line to your `configure.in' file instead of the tests above:
AM_PATH_GSL(GSL_VERSION,
[action-if-found],
[action-if-not-found])
The argument GSL_VERSION should be the two or three digit
MAJOR.MINOR or MAJOR.MINOR.MICRO version number of the release
you require. A suitable choice for action-if-not-found is,
AC_MSG_ERROR(could not find required version of GSL)
Then you can add the variables GSL_LIBS and GSL_CFLAGS to
your Makefile.am files to obtain the correct compiler flags.
GSL_LIBS is equal to the output of the gsl-config --libs
command and GSL_CFLAGS is equal to gsl-config --cflags
command. For example,
libgsdv_la_LDFLAGS = \
$(GTK_LIBDIR) \
$(GTK_LIBS) -lgsdvgsl $(GSL_LIBS) -lgslcblas
Note that the macro AM_PATH_GSL needs to use the C compiler so it
should appear in the `configure.in' file before the macro
AC_LANG_CPLUSPLUS for programs that use C++.