--- /dev/null
+#!/bin/sh
+
+: ${PERL=perl}
+
+case "$PERL" in
+ *'missing perl')
+ echo 1>&2 "$0: configure didn't find a usable version of Perl, so can't run thi
+s test"
+ exit 77
+ ;;
+esac
+
+exec $PERL -w -- - <<\EOF
+
+# Ensure that cat exits upon a single EOF (^D) from a tty.
+use strict;
+
+(my $ME = $0) =~ s|.*/||;
+
+eval { require Expect };
+$@ and (warn "$ME: this script requires Perl's Expect package\n"), exit 77;
+
+{
+ my $fail = 0;
+ foreach my $cmd (qw(md5sum sha1sum cksum cat))
+ {
+ my $exp = new Expect;
+ $exp->log_user(0);
+ $exp->spawn($cmd)
+ or (warn "$ME: cannot run `$cmd': $!\n"), $fail=1, next;
+ $exp->send("foo\n");
+ $exp->send('\ 4'); # FIXME: it'd be better not to hard-code ^D here
+ $exp->expect (0, '-re', "^foo\\r?\$");
+ my $found = $exp->expect (1, '-re', "^.+\$");
+ # $found and warn "F: $found: " . $exp->exp_match () . "\n";
+ $exp->expect(0, 'eof');
+ # defined $exp->exitstatus and warn "E: " . $exp->exitstatus . "\n";
+ defined $found && defined $exp->exitstatus && $exp->exitstatus == 0
+ or (warn "$ME: $cmd didn't exit after ^D from standard input\n"),
+ $fail=1;
+ $exp->hard_close();
+ }
+
+ exit $fail
+}
+EOF