+# Pass EXIT_*, not number, to usage, exit, and error (when exiting)
+# Convert all uses automatically, via these two commands:
+# git grep -l '\<exit *(1)' \
+# | grep -vEf .x-sc_prohibit_magic_number_exit \
+# | xargs --no-run-if-empty \
+# perl -pi -e 's/(^|[^.])\b(exit ?)\(1\)/$1$2(EXIT_FAILURE)/'
+# git grep -l '\<exit *(0)' \
+# | grep -vEf .x-sc_prohibit_magic_number_exit \
+# | xargs --no-run-if-empty \
+# perl -pi -e 's/(^|[^.])\b(exit ?)\(0\)/$1$2(EXIT_SUCCESS)/'
+sc_prohibit_magic_number_exit:
+ @re='(^|[^.])\<(usage|exit) ?\([0-9]|\<error ?\([1-9][0-9]*,' \
+ msg='use EXIT_* values rather than magic number' \
+ $(_prohibit_regexp)
+