
Topic:          'expr' bug in HP-UX 10.x
By:             The MathWorks, Inc.
Date(s):        May 1996 - 29
                Dec 1996 - 16
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$Revision: 1.2 $  $Date: 1996/12/19 02:51:13 $
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1. There is a bug in the /usr/bin/expr command in HP-UX 10.x.
   There is an official patch for HP-UX 10.0 and 10.01. However,
   it is still broken in HP-UX 10.10, and 10.20!

2. Here is the easiest way to fix the problem for any HP-UX 10.x
   system.

   . Become superuser in this directory.

   . Check that the owner and group of the patched 'expr'
     command in this directory is 'bin'.

     Fix this if this is not true using the commands:

        chown bin expr
        chgrp bin expr

   . Copy the 'expr' command to /usr/bin

        cp -p expr /usr/bin/expr

3. For HP-UX 10.0 and 10.01 customers who want to use the standard
   HP patch install process, see the installation instructions in
   the patch, 'PHCO_6194', in this directory.

   There is currently no official patch for HP-UX 10.10.  So use
   step 2. above for this case. Do the same for 10.20.

4. To test the installation run the command at the shell prompt:

        /usr/bin/expr "a" : '\(A\)'

   It should return the empty string NOT a '0'.
