[R] Package updates fail: how to fix the causes

[Rich Shepard]

Running R-3.5.2 on Slackware-14.2, using my script that updates installed
packages found four that failed. My web searches did not find relevant hits,
and only the last build failure is explained by the build failure of a
specific dependency. The results displayed are:

ERROR: dependency ‘sf’ is not available for package ‘spdep’
* removing ‘/usr/lib/R/library/spdep’

The downloaded source packages are in
 	‘/tmp/RtmpzEBBCY/downloaded_packages’
Updating HTML index of packages in '.Library'
Making 'packages.html' ... done
Warning messages:
1: In install.packages(update[instlib == l, "Package"], l, contriburl = contriburl,  :
   installation of package ‘units’ had non-zero exit status
2: In install.packages(update[instlib == l, "Package"], l, contriburl = contriburl,  :
   installation of package ‘later’ had non-zero exit status
3: In install.packages(update[instlib == l, "Package"], l, contriburl = contriburl,  :
   installation of package ‘sf’ had non-zero exit status
4: In install.packages(update[instlib == l, "Package"], l, contriburl = contriburl,  :
   installation of package ‘spdep’ had non-zero exit status

Starting at the top, trying to install 'units' resulted in identifying a
missing library:

Configuration failed because libudunits2.so was not found. Try installing:
     * deb: libudunits2-dev (Debian, Ubuntu, ...)
     * rpm: udunits2-devel (Fedora, EPEL, ...)
     * brew: udunits (OSX)
   If udunits2 is already installed in a non-standard location, use:
     --configure-args='--with-udunits2-lib=/usr/local/lib'
   if the library was not found, and/or:
     --configure-args='--with-udunits2-include=/usr/include/udunits2'
   if the header was not found, replacing paths with appropriate values.
   You can alternatively set UDUNITS2_INCLUDE and UDUNITS2_LIBS manually.
--------------------------------------------------------------------------------
See `config.log' for more details
ERROR: configuration failed for package ‘units’
* removing ‘/usr/lib/R/library/units’

The downloaded source packages are in
 	‘/tmp/RtmprbnasH/downloaded_packages’
Updating HTML index of packages in '.Library'
Making 'packages.html' ... done
Warning message:
In install.packages("units") :
   installation of package ‘units’ had non-zero exit status

Please advise me on how to proceed so these four packages are eventually
updated or re-installed.

TIA,

Rich