compilation of ldap under sco version 3.2

[VIGNAUX Eric <eric.vignaux@sacem.fr>]

I ve got a lot of problems when trying to compile ldap. I had to make
sources modifications, but now, i ve no ideas.
The error message :

undefined                       first referenced

 symbol                             in file

truncate                            replog.o

ftruncate                           rq.o

ld fatal: Symbol referencing errors. No output written to slurpd

*** Error code 13

*** Error code 1

*** Error code 1

*** Error code 1                                             

This is because my system do not have these functions (i ve checked it) . 
May I append these functions to the source code ?
Did i took the wrong way ? In this case, what to do ?

Thank you.