Cannot find pkg-config error

I am trying to install some software on my mac; however I keep receiving the same error:

configure: error: The pkg-config script could not be found or is too old.  Make sure it
is in your PATH or set the PKG_CONFIG environment variable to the full
path to pkg-config.

Alternatively, you may set the environment variables XMEDCON_GLIB_CFLAGS
and XMEDCON_GLIB_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

To get pkg-config, see <http://pkg-config.freedesktop.org/>.
See `config.log' for more details

I am not quite sure how to go about adding the pkg-config to the PATH. I have seen online (see link) that I should add the following:

Link showing how to direct PATH variable

export PATH=$PATH:/opt/local/bin     # Fixed typo as mentioned in comment

which is where I have placed pkg-config. I still keep getting the error though every time I try to configure the files using ./configure. Any help would be super appreciated!

Solution 1:

For Ubuntu/Debian OS,

apt-get install -y pkg-config

For Redhat/Yum OS,

yum install -y pkgconfig

For Archlinux OS,

pacman -S pkgconf

Solution 2:

for me, (OSX) the problem was solved doing this:

brew install pkg-config