Dear SCO Customer,

The enclosed Support Level Supplement (SLS) PTF3088, the SIGCLD Signal
Mapping Supplement, installs an updated set of libraries (libthread).
This updated set of libraries (libthread) contains modifications which
correct a problem that results in child processes becoming defunct when
the signal call is used to ignore the occurrence of the SIGCLD signal.
 
SLS PTF3088 resolves these issues:

1. Using signal (SIGCLD, SIG_IGN) and linking with libthread 
   causes child processes to become DEFUNCT.

2. The behavior did not comply with the signal() ABI.


Software Notes and Recommendations
----------------------------------

PTF3088 should only be installed on these releases:

        SCO UnixWare Application Server Release 2.1.0
        SCO UnixWare Application Server Release 2.1.1
        SCO UnixWare Application Server Release 2.1.2
        SCO UnixWare Personal Edition Release 2.1.0
        SCO UnixWare Personal Edition Release 2.1.1
        SCO UnixWare Personal Edition Release 2.1.2


Installation Instructions
-------------------------

1. Become root and create a new directory by typing the following:
 
     $ su
     Password: <type your root password>
     # mkdir /tmp/pkg
     # chmod 700 /tmp/pkg
     # cd /tmp/pkg

2. Download the ptf3088.Z and the ptf3088.txt files to the newly
   created /tmp/pkg directory on your machine.
 
3. Uncompress the file and add the package to your system using these
   commands:
 
     # uncompress /tmp/pkg/ptf3088.Z
     # pkgadd -d /tmp/pkg/ptf3088 

4. Reboot the system after installing this PTF.


Removal Instructions
---------------------

1. As root, remove the package.

     $ su
     Password: <type your root password>
     # pkgrm ptf3088

2. Reboot the system after removing this PTF.


If you have questions regarding this SLS, or the product on which it is
installed, please contact your software supplier.

We appreciate your business.

SCO Support Services