or download this
karls-mac-mini:hook karl$ perl -MPOSIX=tmpnam -e 1
Unimplemented: POSIX::tmpnam(): use File::Temp instead at /Users/karl/
+perl5/perlbrew/perls/perl-5.26.2/lib/5.26.2/darwin-2level/POSIX.pm li
+ne 185.
...
* perl-5.26.2
karls-mac-mini:hook karl$ perlbrew use perl-5.24.1threads
karls-mac-mini:hook karl$ perl -MPOSIX=tmpnam -e 1