Using make to copy a set of files when directory is referenced.

Hi Carlos.

While I do not have the answer to your question, I could perhaps provide you with a small useful snippet...

I've been messing with GNU make myself, however I'm not an expert. - I even tried to set up BIND once; I'm not sure I succeeded, though.

I think that it's possible to depend on a partial path (including the pathname), thus you'd have to write a rule approximately like this:

$(libdir)/%.o : %.o

     @echo "copy to $(libdir): $< $@"

-You can try it out and see if it's doing what you need (and add the actual copying, once you're sure).

Instead of duplicating all files, on Linux and Unix you can use symbolic links.

So use

    ln -s ${dir} ${dest}

...in order to create a symbolic link to $dir from within $dest.

If you need to generate an entire tree of symbolic links (that's not very likely, I know), the following snippet might come in handy:

It first invokes a subshell (using parantheses), then changes to the directory holding $dir, generates all the directories, and then it fills it with symbolic links to the actual files.

This way you will avoid quickly running out of harddisk space, while still having a protection against accidental file removal.

Note: This is a bash snippet.

    (

        cd "${parentdir}"

        find "${dir}" -type d -exec mkdir "${dest}/"{} \;

        find "${dir}" -type f -exec ln -s {} "${dest}"/{} \;

    )

$parentdir holds the directory containing $dir

$dest is the directory where $dir and its contents will be created.

Please notice: You will have to put the above commands on a single line in your makefile, otherwise it will not work. Something like:

    ( cd "${parentdir}"; find "${dir}" -type d -exec mkdir "${dest}/"{} \; ;find "${dir}" -type f -exec ln -s {} "${dest}"/{} \; )

...And of course, the line starts with  a <TAB>, not spaces.

-But a completely different solution (and probably the correct one) would be to have all your libraries as source code, then build the sources, but output all the .o files to a subdirectory of your project.

Eg. an "output" folder would then contain all the .o files in a directory hierarchy similar to your source hierarchy.

This is definitely possible, but it will require a lot of work and testing.

Hi Carlos.

While I do not have the answer to your question, I could perhaps provide you with a small useful snippet...

I've been messing with GNU make myself, however I'm not an expert. - I even tried to set up BIND once; I'm not sure I succeeded, though.

I think that it's possible to depend on a partial path (including the pathname), thus you'd have to write a rule approximately like this:

$(libdir)/%.o : %.o

     @echo "copy to $(libdir): $< $@"

-You can try it out and see if it's doing what you need (and add the actual copying, once you're sure).

Instead of duplicating all files, on Linux and Unix you can use symbolic links.

So use

    ln -s ${dir} ${dest}

...in order to create a symbolic link to $dir from within $dest.

If you need to generate an entire tree of symbolic links (that's not very likely, I know), the following snippet might come in handy:

It first invokes a subshell (using parantheses), then changes to the directory holding $dir, generates all the directories, and then it fills it with symbolic links to the actual files.

This way you will avoid quickly running out of harddisk space, while still having a protection against accidental file removal.

Note: This is a bash snippet.

    (

        cd "${parentdir}"

        find "${dir}" -type d -exec mkdir "${dest}/"{} \;

        find "${dir}" -type f -exec ln -s {} "${dest}"/{} \;

    )

$parentdir holds the directory containing $dir

$dest is the directory where $dir and its contents will be created.

Please notice: You will have to put the above commands on a single line in your makefile, otherwise it will not work. Something like:

    ( cd "${parentdir}"; find "${dir}" -type d -exec mkdir "${dest}/"{} \; ;find "${dir}" -type f -exec ln -s {} "${dest}"/{} \; )

...And of course, the line starts with  a <TAB>, not spaces.

-But a completely different solution (and probably the correct one) would be to have all your libraries as source code, then build the sources, but output all the .o files to a subdirectory of your project.

Eg. an "output" folder would then contain all the .o files in a directory hierarchy similar to your source hierarchy.

This is definitely possible, but it will require a lot of work and testing.

Hello jensbauer!

I think the "Make" will not meet my expectation, I think what I need is not posível, not yet. I do not think the output is to use a script as the shell to copy files. Well, anyway I see how I will still have to devote to studies of Make.

Well, I have seen this week, by indication of the Livius, the new CMSIS-Pack concept, which seems to be well connected with what I want, I'll see how I can use it and if I can extend it for mining needs without hurting license use.

The advantage of ASF package from Atmel is that it has everything it takes to work with Atmel, AVR or ARM is, and comes CMSIS also, but Atmel has not yet adopted the new CMSIS 4 that defines this packaging approach. And the ASF package is organized so that seems laborious separation of files, maybe I'll make a redistribution of files and place in my repository so it can be downloaded when needed.

Concerning the use of the links, which is undoubtedly the best choice, I always used when programmed in Java, helped me a lot to manage hundreds of packages / framworks of projects without having to keep thousands of copies of jar files on it, but it seems that the GCC plugin or Eclipse CDT does not get along well with links, I have not done deep testing, but already noticed problems when trying to create references for use with my projects. Tutorial in GNU ARM Eclipse Plugin also cites such problem.

Currently I'm using one single library folder, where I have all my LPC libraries (plus one from Freescale and one from ST).

I've generalized my Makefile, so that it allows me to specify a library path, which points to the particular library.

In addition, I've created an output folder (see Freddie Chopin's Makefile for LPC43xx as a reference on how this can be done).

The reason the output-folder is required, is that whenever you build your project, the .o files are usually placed right next to your sources.

If that is the case, and you have two different projects, one that uses Ethernet and one that does not use Ethernet, then you may have to use "make clean" whenever you've just build the other project, in order to get the files up to date. An output folder that belongs to your project would be a good solution to this problem, plus it would speed up building as you can suddenly use dependencies.

I've never had problems with symlinks and GCC. If you have problems with your setup, it may be happening if you're running on Windows, but it would more likely be a problem with Eclipse.

I use symlinks when I build my GCC toolchain, so I'm very confident that GCC can handle it. If you're already on Linux, then I would blame Eclipse.

-The Makefile is capable of doing the copying, but it might be a bit complicated. As you write, it might be an easier solution to use a script for this task.

-If you end up copying files, you may want to take a look at 'man cp'; it'll tell you about the '-R' option for recursively copying the files. I don't think you will need any other switches, but I'll mention the '-n' switch is so that files will not be overwritten, and the '-f' switch is in order to force copying (overwrite target files).

> I've never had problems with symlinks and GCC

unfortunately you cannot create portable project using symlinks, since they are not available on Windows, so I generally do not recommend this solution.

Eclipse references to folders and files can be defined in a portable way, using macros with the project/workspace base address; I'm pretty convinced they can be used for the purpose you mentioned, but they just require some attention.

Carlos, can you point me the tutorial page where Eclipse links are not recommended, to check the content for correctness?

Liviu

I did some tests here and I did not success, just do not find the files. it gave no error besides not find the files.

Of course I am a beginner, and I must be doing something wrong, which I am researching.

The link I saw on synlinks fault with is the following: http://playground.arduino.cc/Code/Eclipse

I don't use Windows, only MAC OS and Linux.

On windows with ntfs has #symlinks, but it is not good, always generates exceptions in the OS, and even screen azull (hehehe), but it exists.

There is a tool to assist the use of symlinks in all versions of windows: http://www.howtogeek.com/howto/16226/complete-guide-to-symbolic-links-symlinks-on-windows-or-linux /

Well, anyway, my environment is *nix, and will not give up. : D