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Debugging failed compilations with apt-file

Thanks to the high standards of many open source projects, I rarely receive compilation errors when ./configureing or makeing a project. When I do receive compilation errors, though, 99% of them are due to a missing header file / function. Ubuntu's apt-file program makes it extremely simple to track down the package containing the header file / function needed by the source you're compiling.

Installing apt-file on Ubuntu

Installaing and configuring apt-file is extremely simple.

$ sudo apt-get install apt-file
$ apt-file update # sudo optional

As hinted in the comment above, you have the choice of using sudo with apt-file. I prefer to not use sudo, but it's really just a personal preference.

Using apt-file to find the right package

Here's a real world compilation error you may come across if you're installing a Python library that uses native extensions:

...c:125: fatal error: Python.h: No such file or directory

So Python.h is some header file, and we need to find what package it belongs to. To search for the package containing this exact file, we do

$ apt-file -x search "/Python.h$"
pypy-dev: /usr/lib/pypy/include/Python.h
python2.7-dbg: /usr/include/python2.7_d/Python.h
python2.7-dev: /usr/include/python2.7/Python.h
python3.2-dbg: /usr/include/python3.2dmu/Python.h
python3.2-dev: /usr/include/python3.2mu/Python.h

The correct package is either pypy-dev, python2.7-dev, or python3.2-dev, depending upon which Python version you have installed. You can install the package via apt-get and finish your compliation.

Let's analyze the apt-file call we did above. The -x flag indicates the pattern string will be a regular expression. This is necessary because just searching for "Python.h" will bring up results like

freecad-dev: /usr/include/freecad/Mod/Part/Gui/ViewProviderPython.h
libsidl-dev: /usr/include/c/sidl_Python.h
libsidl-dev: /usr/include/sidl_Python.h
libvtk5-dev: /usr/include/vtk-5.8/vtkPython.h

(You can see this for yourself by running apt-file search "Python.h")

We then use the regular expression pattern "/Python.h$" to make sure we match the filename exactly (Note the / and the $ symbols).

Here's another example where things weren't so straightforward, but still end up being pretty easy thanks to apt-file and apt-cache.

Here I was initially attempting to compile Vim 7.3.

/tmp/vim73$ ./configure
configure: loading cache auto/config.cache
checking whether make sets $(MAKE)... yes
checking for gcc... gcc
checking whether the C compiler works... yes
checking for tgetent in -ltermlib... no
checking for tgetent in -ltermcap... no
checking for tgetent in -lcurses... no
no terminal library found
checking for tgetent()... configure: error: NOT FOUND!

Compilation failed due to the absence of a function called tgetent(). We can use apt-file to find the package containing this function.

$ apt-file search tgetent
ncurses-doc: /usr/share/man/man3/tgetent.3ncurses.gz
ncurses-doc: /usr/share/man/man3/tgetent_sp.3ncurses.gz

Unfortunately, only documentation packages were found instead of lib/dev packages. We can still use this, though! We know the ncurses-doc package contains documentation regarding tgetent(), so we can then conclude the ncurses package, or some form of it, contains the function. So now let's look for an "ncurses" package. To search for package by its name instead of its contents, we use apt-cache instead of apt-file. We use the --names-only flag to limit our search to only the name of the package and not its description.

$ sudo apt-cache search --names-only "ncurses"
libncurses5 - shared libraries for terminal handling
libncurses5-dbg - debugging/profiling libraries for ncurses
libncurses5-dev - developer's libraries for ncurses
libncursesw5 - shared libraries for terminal handling 
libncursesw5-dbg - debugging/profiling libraries for ncursesw
libncursesw5-dev - developer's libraries for ncursesw
ncurses-base - basic terminal type definitions
ncurses-bin - terminal-related programs and man pages
ncurses-doc - developer's guide and documentation for ncurses

So which one do we choose? Applying the strategy explained above concerning "lib"/"dev" and the simplest package name, our options are libncurses5 and libncurses5-dev. Recall that "dev" packages are more likely to have the function, so libncurses5-dev is our most likely candidate.

After installing the libncurses5-dev package, I was able to successfully compile the project.

Is this really faster than Google?

That's a fair question, to which I answer "usually". If you only get back doc packages from your apt-file search, I would go ahead and Google. Thankfully, most of the time apt-file will return an obvious candidate.

Tagged as ubuntu, utilities

Date published - December 28, 2012