[ovs-discuss] Fwd: Centos 6.3 build from git

[Ben Pfaff]

On Fri, Aug 31, 2012 at 04:23:42PM -0400, rh ev wrote:
> I checked in the /usr/local/share/aclocal-1.12 folder and there is a whole
> bunch of .m4 files in there. How am I supposed to know if this is the
> correct location, or what files I am missing? Also it doesn't look like
> there is one for openssl. Is there a specific one for openssl because
> that's what my install seems to be complaining about.

No, there is no specific m4 file for openssl.  You need to install the
pkg-config m4 files in a place where aclocal can find them.  Here is
what the aclocal manual says on that topic.

6.3.2 Macro Search Path
-----------------------

By default, `aclocal' searches for `.m4' files in the following
directories, in this order:

`ACDIR-APIVERSION'
     This is where the `.m4' macros distributed with Automake itself
     are stored.  APIVERSION depends on the Automake release used; for
     Automake 1.6.x, APIVERSION = `1.6'.

`ACDIR'
     This directory is intended for third party `.m4' files, and is
     configured when `automake' itself is built.  This is
     `@datadir@/aclocal/', which typically expands to
     `${prefix}/share/aclocal/'.  To find the compiled-in value of
     ACDIR, use the `--print-ac-dir' option (*note aclocal Options::).

   As an example, suppose that `automake-1.6.2' was configured with
`--prefix=/usr/local'.  Then, the search path would be:

  1. `/usr/local/share/aclocal-1.6/'

  2. `/usr/local/share/aclocal/'

   As explained in (*note aclocal Options::), there are several options
that can be used to change or extend this search path.

Modifying the Macro Search Path: `--acdir'
..........................................

The most erroneous option to modify the search path is `--acdir=DIR',
which changes default directory and drops the APIVERSION directory.
For example, if one specifies `--acdir=/opt/private/', then the search
path becomes:

  1. `/opt/private/'

   This option, `--acdir', is intended for use by the internal Automake
test suite only; it is not ordinarily needed by end-users.

Modifying the Macro Search Path: `-I DIR'
.........................................

Any extra directories specified using `-I' options (*note aclocal
Options::) are _prepended_ to this search list.  Thus, `aclocal -I /foo
-I /bar' results in the following search path:

  1. `/foo'

  2. `/bar'

  3. ACDIR-APIVERSION

  4. ACDIR

Modifying the Macro Search Path: `dirlist'
..........................................

There is a third mechanism for customizing the search path.  If a
`dirlist' file exists in ACDIR, then that file is assumed to contain a
list of directory patterns, one per line.  `aclocal' expands these
patterns to directory names, and adds them to the search list _after_
all other directories.  `dirlist' entries may use shell wildcards such
as `*', `?', or `[...]'.

   For example, suppose `ACDIR/dirlist' contains the following:

     /test1
     /test2
     /test3*

and that `aclocal' was called with the `-I /foo -I /bar' options.
Then, the search path would be

  1. `/foo'

  2. `/bar'

  3. ACDIR-APIVERSION

  4. ACDIR

  5. `/test1'

  6. `/test2'

and all directories with path names starting with `/test3'.

   If the `--acdir=DIR' option is used, then `aclocal' will search for
the `dirlist' file in DIR.  In the `--acdir=/opt/private/' example
above, `aclocal' would look for `/opt/private/dirlist'.  Again,
however, the `--acdir' option is intended for use by the internal
Automake test suite only; `--acdir' is not ordinarily needed by
end-users.

   `dirlist' is useful in the following situation: suppose that
`automake' version `1.6.2' is installed with `--prefix=/usr' by the
system vendor.  Thus, the default search directories are

  1. `/usr/share/aclocal-1.6/'

  2. `/usr/share/aclocal/'

   However, suppose further that many packages have been manually
installed on the system, with $prefix=/usr/local, as is typical.  In
that case, many of these "extra" `.m4' files are in
`/usr/local/share/aclocal'.  The only way to force `/usr/bin/aclocal'
to find these "extra" `.m4' files is to always call `aclocal -I
/usr/local/share/aclocal'.  This is inconvenient.  With `dirlist', one
may create a file `/usr/share/aclocal/dirlist' containing only the
single line

     /usr/local/share/aclocal

   Now, the "default" search path on the affected system is

  1. `/usr/share/aclocal-1.6/'

  2. `/usr/share/aclocal/'

  3. `/usr/local/share/aclocal/'

   without the need for `-I' options; `-I' options can be reserved for
project-specific needs (`my-source-dir/m4/'), rather than using it to
work around local system-dependent tool installation directories.

   Similarly, `dirlist' can be handy if you have installed a local copy
of Automake in your account and want `aclocal' to look for macros
installed at other places on the system.