This directory contains the sources for the job control library
libjobs.a.  It also contains new versions of three standard system call
interfaces (read, write and ioctl).  These new routines place their
arguments on the stack instead of using a static location.  Thus, they
are reentrant and allow a read or write in a signal-handling routine
while there is an outstanding read or write which will be restarted.
However, the new routines will ONLY work with kernels that support job
control.  Therefore, you have several choices on how to install them.
If you intend to run job control all of the time and don't care that
non-job control binaries aren't runnable without job control in the
kernel, then install these routines in place of the old versions in the
C library with a "make installlibc".  This is the preferred
installation.  If you want to limit use of these routines to programs
that use libjobs, you could just archive them in libjobs.a.  However,
they won't get taken from libjobs.a if a program uses only stdio,
because they won't be undefined until the C library is being searched.
The final option is to force them to be loaded by combining them with
signal.s.  This can be done with a "make libhack.a" (sorry, but it
really is a hack).  The libraries on the distribution tape were made in
this way, since the C library had to work with and without job control.
	There is also a new version of sleep; it simply uses sigset
instead of signal.
	All of these comments apply to the overlay version also.  Make
the overlay library with "make -f Ovmakefile libovjobs.a" or
"make -f Ovmakefile libovhack.a".