Add a 'pre-inst-env' wrapper script to test library before installing.

* pre-inst-env.in: New input file.
* .gitignore: Register its finalized version.
* configure.ac: Register it in AC_CONFIG_FILES.
* doc/guile-udev.texi
(Using this library before it is installed): Document it.

.gitignore

@@ -8,4 +8,5 @@ config.log
 config.status
 configure
 libtool
+pre-inst-env
 TAGS

configure.ac

@@ -109,6 +109,7 @@ AC_SUBST([guilesitedir])
 GUILE_EFFECTIVE_VERSION=`$GUILE -c '(display (effective-version))'`
 AC_SUBST(GUILE_EFFECTIVE_VERSION)
 
+AC_CONFIG_FILES([pre-inst-env], [chmod +x pre-inst-env])
 AC_CONFIG_FILES([Makefile libguile-udev/Makefile build-aux/Makefile])
 AC_CONFIG_FILES([build-aux/m4/Makefile build-aux/am/Makefile doc/Makefile])
 AC_CONFIG_FILES([modules/Makefile modules/udev/Makefile])

doc/guile-udev.texi

@@ -57,6 +57,7 @@ Documentation License.''
 * Introduction::
 * Installing as a system package::
 * Installing from sources::
+* Using this library before it is installed::
 * API Reference::               Appendices
 * Examples::
 * GNU Free Documentation License::  The license of this manual.
@@ -138,6 +139,17 @@ installed in Guile's default path.  But, if you don't know where your
 Guile site directory is, run @command{configure} without the option,
 and it will give you a suggestion.
 
+@node Using this library before it is installed
+@chapter Using this library before it is installed
+
+If you would like to test this Guile extension as you work on it, without
+having to install it, you can use the @file{pre-inst-env} wrapper after having
+configured and built the project, e.g.@:
+
+@example
+./pre-inst-env examples/device-listener.scm
+@end example
+
 @node API Reference
 @chapter API Reference
 

pre-inst-env.in

@@ -0,0 +1,14 @@
+#!/bin/sh
+
+abs_top_srcdir="`cd "@abs_top_srcdir@" > /dev/null; pwd`"
+abs_top_builddir="`cd "@abs_top_builddir@" > /dev/null; pwd`"
+
+GUILE_EXTENSIONS_PATH="$abs_top_builddir/libguile-udev/.libs${GUILE_EXTENSIONS_PATH=:+:}$GUILE_EXTENSIONS_PATH"
+GUILE_LOAD_COMPILED_PATH="$abs_top_builddir${GUILE_LOAD_COMPILED_PATH:+:}$GUILE_LOAD_COMPILED_PATH"
+GUILE_LOAD_PATH="$abs_top_builddir:$abs_top_srcdir${GUILE_LOAD_PATH:+:}:$GUILE_LOAD_PATH"
+export GUILE_EXTENSIONS_PATH GUILE_LOAD_COMPILED_PATH GUILE_LOAD_PATH
+
+PATH="$abs_top_builddir/scripts:$PATH"
+export PATH
+
+exec "$@"