Porting Rsstail onto OpenBSD



Rsstail is a command-line tool that monitors RSS feeds and detects new entries. I found it as I was recently searching for a method to message myself via Telegram whenever there is a new post of slashdot published. Fortunately, slashdot provides an RSS feed to notify readers of its updates. I can integrate rsstail into a service running in the background to check any new entries of the RSS feed and send contents to Telegram.

The service is supposed to run on an OpenBSD server, but rsstail has not been ported onto OpenBSD, which means I have to build it by myself.

Build Libmrss

Since rsstail depends on libmrss, the first step is to build libmrss.

The build process of libmrss relies on the automake and autoconf tool chains, which can be installed through the pkg_add command on OpenBSD, and while installing, select the latest version (i.e. automake-1.16.5 and autoconf-2.71) for the prompt:

$ doas pkg_add automake autoconf

Retrieve the source code of libmrss:

$ git clone --depth 1 https://github.com/bakulf/libmrss

There is a "autogen.sh" file in the source code, which is the script to generate a "configure" file. Note that the version of installed automake and autoconf should be specified:


After that, use the "configure" script to check dependent libraries and generate a Makefile. Note that OpenBSD places all files of any installed package, including its library files if any, into the "/usr/local" directory (e.g. "/usr/local/lib/libcurl.so"). To let the "configure" script find the location of library files that is under the "usr/local" directory, use CPPFLAGS and LDFLAGS to specify the location expicitly :

$ CPPFLAGS="-I/usr/local/include" LDFLAGS="-L/usr/local/lib" ./configure --prefix=/usr/local

Upon successful execution without any issues, a Makefile will be automatically generated, and now we can compile the source code and install output files into the system:

$ make && make install

Build Rsstail

The next step is to build rsstail, which simpler than doing libmrss.

Retrieve the source code of rsstail:

$ git clone --depth 1 https://github.com/folkertvanheusden/rsstail

The source code already includes a Makefile, but several minor modifications are required:

# add the "/usr/local" directory for the library search path
$ sed -i -e '/^LDFLAGS=/ s/=/=-L\/usr\/local\/lib /' -e '/^CFLAGS=/ s/=/=-I\/usr\/local\/include /' Makefile

# replace the library name of iconv
$ sed -i '/^LDFLAGS=/ s/-liconv_hook/-liconv/' Makefile

# change optimization level to 1
$ sed -i '/^CFLAGS=/ s/-O3/-O1/' Makefile

Now that the Makefile has been modified, we can run the make command to compile and install it:

$ make && make install

Thanks for reading :)