how is tgetent defined?

[David J. Camp]

I just extracted the curses-clock.shar archive from comp.unix.questions,
and it gave me an error that certain symboks were undefined, as below.
Fine, I said, I will just use -ltermcap or -lcurses, but neither worked.
Can anyone tell me in what library these symbols are defined?  I am
using a Sun 3/260 running SunOS 4.0.3.  Thank you,  -David-

cc -ltermcap -o gdc -O gdc.c -lcurses
ld: Undefined symbol 
   _tgetent 
   _tgetflag 
   _tgetstr 
   _tputs 
   _tgetnum 
   _tgoto 
*** Error code 1
make: Fatal error: Command failed for target `gdc'

Bitnet:   david at wubios.wustl                ^      Mr. David J. Camp
Internet: david%wubios at wucs1.wustl.edu    < * >    Box 8067, Biostatistics
uucp:     uunet!wucs1!wubios!david          v      660 South Euclid
Washington University (314) 36-23635               Saint Louis, MO 63110
-- 
Bitnet:   david at wubios.wustl                ^      Mr. David J. Camp
Internet: david%wubios at wucs1.wustl.edu    < * >    Box 8067, Biostatistics
uucp:     uunet!wucs1!wubios!david          v      660 South Euclid
Washington University (314) 36-23635               Saint Louis, MO 63110