[Libguestfs] [nbdkit PATCH] Check for python3 first

[Martin Kletzander]

On systems where python is still set to python2 the check will fail even though
it is still completely possible to compile and use nbdkit.

Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
---
 configure.ac                            |  2 +-
 plugins/python/nbdkit-python-plugin.pod | 13 +++++++------
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/configure.ac b/configure.ac
index 5adce7d7bab5..83eefb60ab73 100644
--- a/configure.ac
+++ b/configure.ac
@@ -471,7 +471,7 @@ AC_SUBST([PERL_CFLAGS])
 AC_SUBST([PERL_LDOPTS])
 
 dnl Check for Python 3, for embedding in the python plugin.
-AC_CHECK_PROG([PYTHON],[python],[python],[no])
+AC_PATH_PROGS([PYTHON],[python3 python],[no])
 AC_ARG_ENABLE([python],
     [AS_HELP_STRING([--disable-python], [disable Python embed plugin])],
     [],
diff --git a/plugins/python/nbdkit-python-plugin.pod b/plugins/python/nbdkit-python-plugin.pod
index 321aeb2c3b53..92a03c3cde6c 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -46,14 +46,15 @@ may want to include documentation and globals (eg. for storing global
 state).  Any other top level statements are run when the script is
 loaded, just like ordinary Python.
 
-=head2 Python 2 and Python 3
+=head2 Python versions
 
-The Python plugin has to be compiled for either Python 2 or Python 3
-when building nbdkit.  You can set the C<PYTHON> environment variable
-to the desired interpreter, otherwise nbdkit will use the interpreter
-called C<python> on the current C<$PATH>.  For example:
+Python 2 end of life is 2020-01-01 and nbdkit >= 1.16 no longer
+supports it.  If you want to use Python 2, you will need to use nbdkit
+version 1.14.  You can set the C<PYTHON> environment variable
+to the desired interpreter, otherwise nbdkit will use interpreter
+called C<python3> or C<python> on the current C<$PATH>.  For example:
 
- PYTHON=/usr/bin/python3 ./configure
+ PYTHON=/opt/local/bin/python3 ./configure
 
 To find out which version the Python plugin was compiled for, use the
 I<--dump-plugin> option, eg:
-- 
2.23.0