[PATCH] rename libutil.a to libnotmuch_util.a

[J. Lewis Muir]

On 03/14, David Bremner wrote:
> Apparently some systems (MacOS?) have a system library called libutil
> and the name conflict causes problems.

Hello, David!

For reference, this issue was also discussed in the past at:

  https://notmuchmail.org/pipermail/notmuch/2015/020728.html

Yes, macOS has a system library with that name:

=== macOS Sierra ===
$ ls -alF /usr/lib/libutil*
-rwxr-xr-x  1 root  wheel  77008 Dec 10 03:02 /usr/lib/libutil.dylib*
lrwxr-xr-x  1 root  wheel     13 Sep 23 11:40 /usr/lib/libutil1.0.dylib@ -> libutil.dylib
===

NetBSD does too:

=== NetBSD 6 ===
$ ls -alF /usr/lib/libutil*
-r--r--r--  1 root  wheel  177672 Nov  9 10:58 /usr/lib/libutil.a
lrwxr-xr-x  1 root  wheel      25 Nov  9 11:05 /usr/lib/libutil.so@ -> ../../lib/libutil.so.7.19
lrwxr-xr-x  1 root  wheel      25 Nov  9 11:05 /usr/lib/libutil.so.7@ -> ../../lib/libutil.so.7.19
lrwxr-xr-x  1 root  wheel      25 Nov  9 11:05 /usr/lib/libutil.so.7.19@ -> ../../lib/libutil.so.7.19
-r--r--r--  1 root  wheel  184398 Nov  9 10:58 /usr/lib/libutil_p.a
-r--r--r--  1 root  wheel  187056 Nov  9 10:58 /usr/lib/libutil_pic.a
===

I'm almost certain NetBSD 7 and current have it too, and FreeBSD too,
but I don't have access to running versions of these to be 100% sure.
Here are some source code pointers:

* macOS
  https://opensource.apple.com/release/os-x-1012.html
  https://opensource.apple.com/source/libutil/libutil-47/

* NetBSD
  http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libutil/?only_with_tag=MAIN

* FreeBSD
  https://svnweb.freebsd.org/base/head/lib/libutil/

Regards,

Lewis