usr/src/lib/libc/db/PORT/README

#       @(#)README      5.3 (Berkeley) %G%

This is the directory to use for creating a library of the dbopen(3)
routines.  The Makefile builds the base system.  By changing it and
the compat.h file, you should be able to pick and choose the various
things your system needs to make libdb run.

The knobs that you may have to turn:

In the Makefile:
        If you don't have mktemp(3) or mkstemp(3) on your system, add
        "mktemp.o" to the MISC list.

        If you don't have snprintf(3) on your system, add snprintf.o
        to the MISC list.

        If you don't have memmove(3), add memmove.o to the MISC list.

In include/compat.h:
        Before attempting to build this library, you should skim through
        the compat.h file, and adjust it as necessary for your system.
        It's possible to use the #ifndef construct to figure out if a
        #ifdef has been set, but C provides no similar method to figure
        out if a typedef has been done.  All of the typedef's are grouped
        at the top of compat.h, your compile errors will tell you which
        ones you need.

        Particularly subtle problems can occur if you don't have the
        BYTE_ORDER set right or if the realloc define is wrong.

Some other problems:
        You may see warning messages about illegal pointer combinations.
        It's because systems prototype malloc, calloc and realloc in
        different places.  If you want to stop the warnings, find out
        where your system prototypes them, and include it in compat.h,
        or, just prototype them yourself.

To install:
        Programs using the dbopen(3) interface have to include db.h.
        To install the library, you'll need to put db.h (found in the
        directory PORT/include) and the library libdb.a in some place
        accesible to your program.

Hints:
        SunOS 4.1.2 works with ``MISC=realloc.o snprintf.o memmove.o''
        and the include/compat.h realloc ``#if 0'' changed to ``#if 1''.
        SunOS gives a bunch of warning messages on the malloc family
        routines.

        Ultrix 4.2A works with ``MISC=realloc.o snprintf.o memmove.o''
        and the include/compat.h realloc ``#if 0'' changed to ``#if 1''
        and BYTE_ORDER changed from BIG_ENDIAN to LITTLE_ENDIAN.
        Ultrix does not give warning messages on the malloc family
        routines.

        The recno routines require the mmap(2) call.  It wouldn't be
        difficult to port this package to a system without mmap.  Change
        rec_open.c to do slightly different initialization and to write
        two new routines for rec_get.c that handle regular files using
        reads and writes.