Some versions of autoconf (eg, the one included with Ubuntu 20.04 -
which is GNU Autoconf 2.69) will produce a configure script that
requires finding the install-sh script in either a short list of parent
directories or the defined AUX_DIR (This new requirement was probably
triggered by the use of the cross-compile features in configure.ac)
Newer versions flexibly identify which of the support scripts are
actually needed (from the list of config.guess, config.sub, install-sh)
and only check for those ones that are needed.
When the `./autogen.sh` runs `autoreconf -i`, it should have copied the
required aux scripts, but for some reason this is not happening.
Once we are not supporting the older autoconf, we should revisit this
config option as these auxiliary scripts should normally not be checked
into a version control system, for the same reasons that configure
shouldn’t be. For now, we ensure that all three scripts are available
and we have set the AC_CONFIG_AUX_DIR() to point to them
If the older autoconf is used, it will report the error:
configure: error: cannot find install-sh, install.sh, or shtool in "." "./.." "./../.."
Which is included here for search engines.
