PostgresSQL on QNX 4
--------------------
last updated:           $Date: 2001/05/24 15:53:31 $

current maintainer:     Bernd Tegge (tegge@repas-aeg.de)
original author:        Andreas Kardos (kardos@repas-aeg.de)

This port is an important step because PostgreSQL is now the only free
relational database with full SQL and ODBC support available for QNX 4.
The only commercial databases available are Empress RDBMS and Velocis
Database Server (not supported for Digital Unix).

The most effort required the emulation of System V semaphore sets,
shared memory and IPC and of some IEEE floating-point functionality.

It is recommended to use the GNU C compiler instead of the Watcom compiler
because the Watcom compiler doesn't support a int8 datatype (long or
long long int) and it does not have a C++ frontend. The only advantage
using Watcom C would be support of Tk and pgaccess.

QNX 4 does not offer native support of shared libraries. Therefore the related
functionality cannot be used. Shared library support could probably be
implemented in future.

QNX 4 does not support UNIX domain sockets. Clients must use TCP/IP sockets.
Therefore postmaster must always be started with the -i option. Furthermore
it would be useful to set the PGHOST variable.

Prerequisites:
--------------

The following prerequisites have been used:

QNX standard:
QNX 4.25, Watcom C 10.6, GNU make

Available from http://www.teaser.fr/~jcmichot/
flex-2.5.4a.tar.gz (flex)
egcs-112-qnx4-r20.tar[.gz] (GNU C)

Available from ftp://ftp.visi.com/users/hawkeyd/qnx/
bison-1.2.5.tar.gz

Available from http://quics.qnx.com/cgi-bin/dir_find.cgi?/usr/free/
perl 5.004_04

from ftp://ftp.freesoftware.com/pub/infozip/zlib/
zlib 1.1.3

tcl8.0.3.tar.Z (Tcl)

In order to achieve meaningful results for the regression tests, you need
a different shell. The standard QNX shell is quite broken with regard to
scripting (even QSSL suggested to use pdksh or bash). Both are available
in source and binaries at
http://quics.qnx.com/cgi-bin/dir_find.cgi?/usr/free/

flex can be built without any problems using the Watcom or GNU C compilers.

The current version of bison (1.2.8 at the time of this writing) does not
build cleanly on QNX4 with gcc installed, but you can download src and
binary of a previous version from the above mentioned ftp site.

download source
GNU C can be installed by
/etc/install -u egcs112-qnx4-r20.tar[.gz]

Although Tcl can be built after some slight code changes using the Watcom
compiler, the GNU C compiler should be used instead. Otherwise it would be
impossible to link postgres built with GNU C together with libtcl8.0.a built
with the Watcom compiler. However, if you are going to build a Watcom version
you must build the tcl and tk libraries with Watcom too.

To make unix/tclUnixTest.c compilable uncomment
#include <sys/resource.h>
in it or
touch /usr/include/sys/resource.h
In unix/Makefile.in replace
	( echo cd $(TOP_DIR)/tests\; source all ) | ./tcltest
by
	( echo cd ../tests\; source all ) | ./tcltest
After that Tcl can be built and tested as stated in README.

Tk cannot be built with GNU C due to the lack of a stack version of the
X11 library. With the Watcom compiler Tk could be built but this is not useful
because of the link problems mentioned above.

Therefore the Tk interface and the pgaccess tool cannot be supported for a GNU C
version of PostgreSQL on QNX 4.

PostgreSQL:
-----------

On QNX 4 some headers are not in the directories expected. To avoid
modifications of the code the following links should be made:

ln -s /usr/local/bin/perl /usr/local/bin/perl5
ln -s /usr/include/errno.h /usr/include/sys/errno.h
ln -s /usr/include/ioctl.h /usr/include/sys/ioctl.h
ln -s /usr/src/pgsql/src/backend/port/qnx4/ipc.h /usr/include/sys/ipc.h
ln -s /usr/src/pgsql/src/backend/port/qnx4/sem.h /usr/include/sys/sem.h
ln -s /usr/src/pgsql/src/backend/port/qnx4/shm.h /usr/include/sys/shm.h

For ecgs-2.91.60 the file
/usr/local/lib/gcc-lib/i386-pc-qnx4/egcs-2.91.66/include/g++/stl_alloc.h
had to be patched (extern "C++" { ... } // extern "C++").
See attached patch.

If all prerequisites are available postgres can be built and installed by
cd pgsql/src
./configure --with-tcl --without-tk --with-perl
gmake > make.log 2>&1
gmake install > make.install.log 2>&1
su
cd interfaces/perl5
gmake install
exit

All other steps can be carried out as stated in the INSTALL file.

Make problems:
--------------

Sometimes the Watcom library manager wlib crashes with SIGSEGV on some
object files. This is a general problem and not PostgreSQL related.
Currently bootstrap.o causes such a crash. The workaround is not to include
the object file into the SUBSYS.o but link it directly. For further information
see backend/Makefile and backend/bootstrap/Makefile.
libpgsql.a currently cannot be generated because of the same problem. But this
doesn't matter since shared libraries are not supported.

Currently yacc fails on backend/parser/gram.y and 
interfaces/ecpg/preproc/preproc.y due to exceeded maximum table size. You can
generate the gram.h, parse.h, preproc.h and preproc.c files on another platform
and use them. This is only a problem when you use the current source tree since
parse.h, gram.c, preproc.h and preproc.c are included in official
distributions. In order to avoid this, install the bison binary mentioned
above.

Regression tests:
-----------------
please don't use the QNX shell for the parallel regression tests. Download
bash from quics.qnx.com and run 'make SHELL=/usr/local/bin/bash check'
instead.

The majority of regression tests succeeded. The following tests failed:

geometry:
Some slight deviation in the last digit and "0" instead of "-0".
Can be ignored.

timestamp, tinterval, abstime, horology:
Differences for years outside the normal Unix range, e.g. 1968
instead of 2105
Can be ignored.

rules:
"ERROR:  Bad money external representation ..."
if a value of type money is inserted in string representation e.g. as in
"insert into rtest_emp values ('wiech', '5000.00');"
Subject of further investigation.

create_function_1, create_function_2, create_type, create_operator,
create_view, select_views, triggers, misc, plpgsql:
Error messages due to the lack of shared library support.

numeric, numeric_big, sanity_check:
"ERROR:  Cannot create unique index. Table contains non-unique values"
This error occurs for indices of tables num_exp_add, num_exp_sub,
num_exp_div and num_exp_mul only.
Subject of further investigation. Probably because of the missing indices
these numeric tests take a long time.
The diffence in sanity_check.out is a consequence of this problem only.

The current state of this port should be sufficient for lot of applications.

The Watcom version failed additional tests because of the lack of int8
support.

Have fun!

Andreas Kardos
2000-04-04

Bernd Tegge
tegge@repas-aeg.de
2001-03-01

---------------------------------------------------------------------------

*** ./stl_alloc.h.orig	Sat Feb 28 05:17:28 1998
--- ./stl_alloc.h	Tue Nov 23 04:14:09 1999
***************
*** 120,125 ****
--- 120,126 ----
  #pragma set woff 1174
  #endif
  
+ extern "C++" {
  // Malloc-based allocator.  Typically slower than default alloc below.
  // Typically thread-safe and more storage efficient.
  #ifdef __STL_STATIC_TEMPLATE_MEMBER_BUG
***************
*** 682,687 ****
--- 683,689 ----
  # endif
  
  #endif /* ! __USE_MALLOC */
+ } // extern "C++"
  
  #if defined(__sgi) && !defined(__GNUC__) && (_MIPS_SIM != _MIPS_SIM_ABI32)
  #pragma reset woff 1174

