Merge pull request #1182 from junghans/pkgconfig_doc

# pkg-config file for lammps

# https://people.freedesktop.org/~dbn/pkg-config-guide.html

# Usage: cc `pkg-config --cflags --libs liblammps` -o myapp myapp.c

# after you added @CMAKE_INSTALL_FULL_LIBDIR@/pkg-config to PKG_CONFIG_PATH,

# Add the directory where lammps.pc got installed to your PKG_CONFIG_PATH

# e.g. export PKG_CONFIG_PATH=@CMAKE_INSTALL_FULL_LIBDIR@/pkgconfig

# Use this on commandline with:

# c++ `pkg-config --cflags --libs lammps` -o myapp myapp.cpp

# Use this in a Makefile:

# myapp: myapp.cpp

# 	$(CC) `pkg-config --cflags --libs lammps` -o $@ $<

# Use this in autotools:

# configure.ac:

# PKG_CHECK_MODULES([LAMMPS], [lammps])

# Makefile.am:

# myapp_CFLAGS = $(LAMMPS_CFLAGS)

# myapp_LDADD = $(LAMMPS_LIBS)

# Use this in CMake:

# CMakeLists.txt:

# find_package(PkgConfig)

# pkg_check_modules(LAMMPS IMPORTED_TARGET lammps)

# target_link_libraries(<lib> PkgConfig::LAMMPS)

prefix=@CMAKE_INSTALL_PREFIX@

libdir=@CMAKE_INSTALL_FULL_LIBDIR@

includedir=@CMAKE_INSTALL_FULL_INCLUDEDIR@