Re: [autoconf] Program & Library, dev in parallel?

[mpsuzuki]

On Wed, 10 Mar 2010 06:05:11 -0500
"Patrick M. Rutkowski" <address@hidden> wrote:

>On Wed, Mar 10, 2010 at 5:24 AM,  <address@hidden> wrote:
>> A possible approarch might be "install-only-different-files".
>> "install" of GNU coreutils has an option "-p" to preserve the
>> timestamp of source file. If it works well, although all headers
>> & libraries are reinstalled, the timestamps of unchanged files
>> are not updated, so rebuilding of the application would be
>> minimized.
>
>You mention this "install-only-different-files"? What exactly is that?
>I can't find docs anywhere. install(1)'s -p option looks like it just
>blindly neglects to update the timestamp, I don't think it actually
>checks the file content to see if things have changed.

I'm sorry for my wrong wording. Yes, "-p" does not check the
content of the files. The scenario I thought was:

* "install -p" sets the mtime of installed file with its
  source file.

* if the source file is not changed after previous installation,
  its mtime is not changed after previous installation.

* even when the file is re-installed, if its mtime is not updated,
  make cannot detect the re-installation of the file.

* therefore, building of application after re-installation of
  library would be minimized for the updated part only.

Regards,
mpsuzuki