nosuchtool 2>/dev/null [ $? -ne 127 ] && exit 1 /var/empty/nosuchtool 2>/dev/null [ $? -ne 127 ] && exit 1 (nosuchtool) 2>/dev/null [ $? -ne 127 ] && exit 1 (/var/empty/nosuchtool) 2>/dev/null [ $? -ne 127 ] && exit 1 / 2>/dev/null [ $? -ne 126 ] && exit 1 PATH=/usr bin 2>/dev/null [ $? -ne 126 ] && exit 1 dummy=$(nosuchtool 2>/dev/null) [ $? -ne 127 ] && exit 1 dummy=$(/var/empty/nosuchtool 2>/dev/null) [ $? -ne 127 ] && exit 1 dummy=$( (nosuchtool) 2>/dev/null) [ $? -ne 127 ] && exit 1 dummy=$( (/var/empty/nosuchtool) 2>/dev/null) [ $? -ne 127 ] && exit 1 dummy=$(/ 2>/dev/null) [ $? -ne 126 ] && exit 1 dummy=$(PATH=/usr bin 2>/dev/null) [ $? -ne 126 ] && exit 1 exit 0