[Gdb] comple gdbm error

[Oliveiros Peixoto]

I am trying to compile gdbm however when I execute make progs it returns me an 
error

bash-2.05b# make progs
gcc  -o tndbm tndbm.o -lc
tndbm.o(.text+0x130): In function `main':
: warning: the `gets' function is dangerous and should not be used.
tndbm.o(.text+0x8c): In function `main':
: undefined reference to `dbm_open'
tndbm.o(.text+0x176): In function `main':
: undefined reference to `dbm_fetch'
tndbm.o(.text+0x22b): In function `main':
: undefined reference to `dbm_store'
tndbm.o(.text+0x28e): In function `main':
: undefined reference to `dbm_delete'
tndbm.o(.text+0x2c7): In function `main':
: undefined reference to `dbm_firstkey'
tndbm.o(.text+0x316): In function `main':
: undefined reference to `dbm_fetch'
tndbm.o(.text+0x35d): In function `main':
: undefined reference to `dbm_nextkey'
tndbm.o(.text+0x3a8): In function `main':
: undefined reference to `dbm_fetch'
tndbm.o(.text+0x3df): In function `main':
: undefined reference to `dbm_firstkey'
tndbm.o(.text+0x404): In function `main':
: undefined reference to `dbm_nextkey'
tndbm.o(.text+0x49a): In function `main':
: undefined reference to `dbm_close'
collect2: ld returned 1 exit status
make: *** [tndbm] Error 1
bash-2.05b# 

any idea?
thank