+cmd="${MH_TEST_DIR}/Mail/cmd"
+
+#### Hack: especially on multicore/multiprocessor machines, need
+#### to allow time for the output file to be closed. If the output
+#### file never reaches a size greater than zero after waiting for
+#### a short while, let a subsequent check fail to find what it needs.
+#### $1: pid to wait for
+#### $2: output file that must eventually have non-zero size
+wait_for_script() {
+ wait $1
+
+ for i in 1 2 3 4 5 6 7 8 9 10; do
+ test -s "$2" && break || sleep 1
+ done
+}
+
+
+if script -S /bin/sh 'echo OK' /dev/null 2>&1 | egrep 'OK' >/dev/null; then
+ #### script(1) uses -S to set the shell that it runs.
+ use_dash_S=1
+else
+ cat >"${cmd}" <<EOF
+#! /bin/sh
+echo OK
+EOF
+ chmod +x "${cmd}"
+
+ (SHELL="${cmd}"; export SHELL; script "${actual}" >/dev/null &
+ wait_for_script $! "${actual}")
+ if grep OK "${actual}" >/dev/null; then
+ #### script(1) supports SHELL environment variable.
+ use_dash_S=0
+ else
+ test_skip "can't find mechanism to set SHELL for script(1)"
+ fi
+fi
+
+#### Run a command but don't wait for user input. script(1) seems to do
+#### what we want by not waiting when run in the background. But check
+#### that it makes the command look like it's connected to a terminal below.
+run_without_input() {
+ #### Create a command to use as a shell for script.
+ cat >"${cmd}" <<EOF
+#! /bin/sh
+$*
+EOF
+ chmod +x "${cmd}"
+
+ if [ ${use_dash_S} -eq 1 ]; then
+ script -S "${cmd}" "${actual}" >/dev/null &
+ else
+ SHELL="${cmd}" script "${actual}" >/dev/null &
+ fi
+
+ wait_for_script $! "${actual}"
+}
+
+#### Ensure that script(1) makes the program look like it's connected to a
+#### terminal. The welcome message code in sbr/utils.c needs that.
+run_without_input 'if test -t 0 -a -t 1 -a -t 2; then echo tty; fi'
+grep tty "${actual}" >/dev/null || test_skip "script(1) doesn't simulate tty"
+