The at now command does not work.

    echo "date" | at now

will never schedule execution. It seems that the job is
scheduled a few seconds *before* the current time.

As a consequence the 'batch' command does not work as it is
a script that executes at now.

Interestingly I have seen this same bug in IRIX,CLIX,AIX,
etc. The solution is to add 1 or 2 minutes depending on
the version of UNIX. This is because some at commands only
schedule to the nearest minute boundary viz

    echo "date" | at now + 2 minutes