-if type xsource &>/dev/null ; then
- xsource "${HOME}/.zshrc.global"
-else
- . "${HOME}/.zshrc.global"
-fi
+
+# Note, that xsource() is defined in the global file, so here,
+# we will have to do the sourcing manually for once:
+
+ [[ -z "$ZSHRC_GLOBAL_HAS_BEEN_READ" ]] \
+ && [[ -r "${HOME}/.zshrc.global" ]] \
+ && source "${HOME}/.zshrc.global"