xjobs reads job descriptions line by line and executes them in parallel. It
limits the number of parallel executing jobs and starts new jobs when jobs
finish. Therefore, it combines the arguments from every input line with the
utility and arguments given on the command line. If no utility is given as
an argument to xjobs, then the first argument on every job line will be used
as utility. To execute utility xjobs searches the directories given in the
PATH environment variable and uses the first file found in these directories.

xjobs is most useful on multiprocessor machines when one needs to execute
several time consuming commands that could possibly be run in parallel. With
xjobs this can be achieved easily, and it is possible to limit the load of
the machine to a useful value. It works similar to xargs, but starts several
processes simultaneously and gives only one line of arguments to each utility
call.