Make this script relocatable again: derive a relative path for the

original installation prefix from the examples prefix.  Use that
relative path to locate the current installation prefix, always.  Fall
back to an absolute installation prefix if the relative path cannot be
derived.

1 files changed, 25 insertions, 2 deletions

diff --git a/examples/run-c-ex.sh.in b/examples/run-c-ex.sh.in
index ffb01bc..82050a1 100644
--- a/examples/run-c-ex.sh.in
+++ b/examples/run-c-ex.sh.in
@@ -28,10 +28,33 @@
 # Initializations
 EXIT_SUCCESS=0
 EXIT_FAILURE=1
- 
+
+#
+# Try to derive the path to the installation $prefix established
+# by ./configure relative to the examples directory established by
+# ./configure.  If successful, set `prefix_relto_examplesdir` to the
+# relative path.  Otherwise, set `prefix_relto_examplesdir` to the
+# absolute installation $prefix.
+#
+# This script uses the value of `prefix` in the user's environment, if
+# it is set, below.  The content of $() is evaluated in a sub-shell, so
+# if `prefix` is set in the user's environment, the shell statements in
+# $() won't clobbered it.
+#
+prefix_relto_examplesdir=$(
+prefix=@prefix@
+examplesdir=@examplesdir@
+if [ ${examplesdir##${prefix}/} != ${examplesdir} ]; then
+	echo $(echo ${examplesdir##${prefix}/} | \
+	    sed -E 's,[^/]+,..,g')
+else
+	echo $prefix
+fi
+)
+
 # Where the tool is installed.
 # default is relative path to installed location of the tools 
-prefix="${prefix:-@prefix@}"
+prefix="${prefix:-${prefix_relto_examplesdir}}"
 PARALLEL=@PARALLEL@             # Am I in parallel mode?
 AR="@AR@"
 RANLIB="@RANLIB@"