arning by compile postgres6.3.2 source

Hi,
 Postgres6.3.2 was successfully installed and I can start psql-monitor.
 plattform is: SunOS 5.5.1 Generic_103640-12 sun4u sparc SUNW,Ultra-1

but there are  warning by compile postgres6.3.2 source  like :
postmaster.c:307: warning: implicit declaration of function
`gethostname'
postmaster.c:1287: warning: implicit declaration of function `srandom'
postmaster.c:1291: warning: implicit declaration of function `random'
fe-connect.c:561: warning: passing arg 4 of `setsockopt' from
incompatible pointer type
ecpglib.c:673: warning: int format, pid_t arg (arg 3)

I have link-Problem in C-Program.

% gcc -o testlibpq testlibpq.o -L/home/stud-1/kheldoun/pgsql/lib  -lpq

I get the following message:
Undefined                       first referenced
 symbol                             in file
socket
/home/stud-1/kheldoun/pgsql/lib/libpq.a(fe-connect.o)
getprotobyname
/home/stud-1/kheldoun/pgsql/lib/libpq.a(fe-connect.o)
gethostbyname
/home/stud-1/kheldoun/pgsql/lib/libpq.a(fe-connect.o)
setsockopt
/home/stud-1/kheldoun/pgsql/lib/libpq.a(fe-connect.o)
getsockname
/home/stud-1/kheldoun/pgsql/lib/libpq.a(fe-connect.o)
connect
/home/stud-1/kheldoun/pgsql/lib/libpq.a(fe-connect.o)
ld: fatal: Symbol referencing errors. No output written to testlibpq
*** Error code 1
make: Fatal error: Command failed for target `testlibpq'

......
can you help please ?

Thanks