[R-pkg-devel] set PKG_CONFIG_PATH before installing a package

[Dirk Eddelbuettel]

On 8 April 2019 at 10:59, Travers Ching wrote:
| I think the correct way to do it is through the configure script.  See
| for example the Cairo package that uses pkg-config.  Configure scripts
| are slightly hard to work through in my experience, but are worth it
| if you need  customization of the installation environment.

Or from the RcppRedis package you and I stand behind :)

[...]

## ... but check for pkg-config
AC_DEFUN([AC_PROG_PKGCONFIG], [AC_CHECK_PROG(PKGCONFIG,pkg-config,yes)])
AC_PROG_PKGCONFIG

## use pkg-config for hiredis
##
if test x"${PKGCONFIG}" == x"yes"; then
    ## check via pkg-config for hiredis
    if pkg-config --exists hiredis; then
        ## obtain cflags and obtain libs
        hiredis_cxxflags=`pkg-config --cflags hiredis`
        hiredis_libs=`pkg-config --libs hiredis`
        ## no need to build libhiredis.a
        hiredis_tgt=""     
    else
        AC_MSG_WARN([pkg-config exists but hiredis is not available.])
    fi
fi

## And make sure these flags are used for the tests below.
CPPFLAGS="${hiredis_cxxflags} ${CPPFLAGS}"
CXXFLAGS="${hiredis_cxxflags} ${CXXFLAGS}"

[...]

There is more at
  https://github.com/eddelbuettel/rcppredis/blob/master/configure.ac 
but is a key part.


Another useful trick is to just write a shell script 'configure' as one does
not have to use 'autoconf' to produce 'configure' see eg
  https://github.com/Rblp/Rblpapi/blob/master/configure
for that approach, or one of Jeroen's packages.


Last but not least you can call 'pkg-config' directly from src/Makevars too.

Dirk

-- 
http://dirk.eddelbuettel.com | @eddelbuettel | edd using debian.org