X-Git-Url: https://sipb.mit.edu/gitweb.cgi/ikiwiki.git/blobdiff_plain/81a7c9754ee07130f4375364545255d0a38bdc05..27261da09be059c6400d71138f060eb94faa407e:/doc/bugs/PREFIX_not_honoured_for_underlaydir.mdwn

diff --git a/doc/bugs/PREFIX_not_honoured_for_underlaydir.mdwn b/doc/bugs/PREFIX_not_honoured_for_underlaydir.mdwn
index a8ae17995..11557c822 100644
--- a/doc/bugs/PREFIX_not_honoured_for_underlaydir.mdwn
+++ b/doc/bugs/PREFIX_not_honoured_for_underlaydir.mdwn
@@ -14,4 +14,31 @@ However when I try to run ikiwiki I get an error as follows:
 Can't stat /usr/share/ikiwiki/basewiki: No such file or directory 
  at /home/ed/lib/perl5/site_perl/5.8.7/IkiWiki/Render.pm line 349 
 
-The PREFIX specified at build time should also affect the share directory - it shouldn't try to use /usr/share here.
\ No newline at end of file
+The PREFIX specified at build time should also affect the share directory -
+it shouldn't try to use /usr/share here.
+
+> Actually, the PREFIX, no matter where you specify it, is only
+> intended to control where files are _installed_, not where they're
+> looked for at runtime.
+
+> There's a good reason not to make PREFIX be used to actually
+> change the program's behavior: Most packaging systems use PREFIX
+> when building the package, to make it install into a temporary
+> directory which gets packaged up.
+
+This is not the case.  That is the difference between PREFIX and DESTDIR.
+
+DESTDIR does what you describe; it causes the files to be installed into some
+directory you specify, which may not be the same place you'd eventually
+run it from.
+
+PREFIX means build the software to run under the location given.  Normally it
+will also affect the location files are copied to, so that 'make install'
+installs a working system.
+
+At least, that's the way I've always understood it; the MakeMaker documentation
+isn't entirely clear (perhaps because ordinary Perl modules do not need to be
+configured at build time depending on the installation directory).  It does mention
+that DESTDIR is the thing used by packaging tools.
+
+> Thanks for clarifying that. [[bugs/done]] --[[Joey]]