SRDB ID: 3886  
SYNOPSIS: Using DNS without NIS

DETAIL DESCRIPTION:

Want to use DNS, but not NIS

SOLUTION SUMMARY:

MAKING A LIBC.SO for DNS without NIS

This is a procedure that can be used to add name resolver
routines into shared libc library in SunOS_4.1.

First load "SHLIB CUSTOM" either from SunInstall or from
add_services.  Besure to have the file /etc/resolv.conf 
configured properly. 

Test this with /usr/etc nslookup.

1. Become superuser**
     % su  (if necessary)

 2. Make a temporary directory:

     % cd /usr/lib/shlib.etc
     % mkdir tmp

3. Change to the "tmp" directory just made, extract the pic .o
    from libc_pic.a and rm the file __.SYMDEF. The 
    reason you need to do the 2 "mv" commands is 
    because "ar" truncated filenames over 16 characters.

     % cd tmp
     % ar x ../libc_pic.a
     % rm __.SYMDEF
     % mv rpc_dtablesize. rpc_dtablesize.o
     % mv rpc_commondata. rpc_commondata.o
    % mv xccs.multibyte. xccs.multibyte.o
     % ar x /usr/lib/libresolv.a

     The libresolv.a (apparently) contains object modules 
    position independant, so they can be added to 
    the libc_pic modules without fear.

 4. Remove the old routine to do the hostname/addr resolution:             (might not be there in 1.1.4)

     % rm gethostent.o

 5. Remove the libresolv module that contains `strncasecmp'
    (which is now in the main C library, 
    so it is redundant):

     % rm strcasecmp.o

 6. Backup a directory

    % cd ..

 7. Copy lorder-sparc to lorder-sparc.orig.  Edit the 
    file lorder-sparc and remove the reference 
    to `gethostent.o' and add the references to the
    resolver library routines by applying this patch:

     remove:    
        gethostent.o

    add:    
        gethostnamadr.o 
         sethostent.o 
         res_query.o 
         res_mkquery.o 
         res_send.o 
         res_debug.o 
         res_comp.o 
         res_init.o


     % diff -rc2 lorder-sparc.orig lorder-sparc
     *** lorder-sparc.orig   Thu Feb  8 05:27:46 1990
     --- lorder-sparc    Mon Apr  9 12:58:59 1990
     ***************
     *** 150,154 ****
       getwd.o
       getnetgrent.o
     ! gethostent.o
       ypxdr.o
       ttyname.o
     --- 150,161 ----
       getwd.o
       getnetgrent.o
     ! gethostnamadr.o
     ! sethostent.o
     ! res_query.o
     ! res_mkquery.o
     ! res_send.o
     ! res_debug.o
     ! res_comp.o
     ! res_init.o
       ypxdr.o
       ttyname.o


 8. Edit the Makefile

    Change OBJSORT line to include the local directory "."
    Apparently this is needed if you are root (i didn't
    need to do this on my 4.1.3 build)

    OBJSORT=./objsort

    For SunOS 4.1.3 (at least) you need to add -ldl to
    the end of ld command in the two targets.  If you
    don't do this you are forced to link dl with all
    executables you create with the c compiler

    % make libc.so

 9. Now a new libc libc.so.x.y.z is built in the current 
    directory.  It is recommended that you test 
    out this library at this point before installing it.  
    Can do so by setting the environment LD_LIBRARY_PATH 
    to the current directory, for

    example:

    % setenv LD_LIBRARY_PATH `pwd`
    % your_favorite_test_cmd  (ie. ping, ftp, telnet)

    Once satisfied that the new library worked, proceed to
    install it with the following commands:

     % cp libc.so.x.y.z /usr/lib
     % ldconfig
     % unsetenv LD_LIBRARY_PATH

10. Now running with the new library.  Verify this by 
    doing a trace command
    of let's say "date".

 % trace date

The output should inform you that the new library 
is being used.

 BUG REPORT ID: n/a
 PATCH ID: n/a
 PRODUCT AREA: n/a
 PRODUCT: DNS
 SUNOS RELEASE: SunOS 4.1
 UNBUNDLED RELEASE: n/a
 HARDWARE: n/a