Including the header is not enough.... you must also link your binary against the library.
On Feb 11, 2008, at 9:52 PM, Shwe Yee Than wrote:
Hello,
I´ve got a problem when trying to access Postgresql through C language. I've included "libpq-fe.h" as a header file in the C program. When I compile it, I got the following errors:
[srb@fsktm src]$ gmake alpha1.o(.text+0x297c6):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12726: undefined reference to `PQstatus' alpha1.o(.text+0x297f5):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12729: undefined reference to `PQerrorMessage' alpha1.o(.text+0x2986f):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12741: undefined reference to `PQexec' alpha1.o(.text+0x29886):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12743: undefined reference to `PQresultStatus' alpha1.o(.text+0x298b2):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12746: undefined reference to `PQclear' alpha1.o(.text+0x298c3):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12747: undefined reference to `PQfinish' alpha1.o(.text+0x298e8):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12751: undefined reference to `PQntuples' alpha1.o(.text+0x2990c):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12752: undefined reference to `PQgetvalue' alpha1.o(.text+0x29935):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12754: undefined reference to `PQclear' alpha1.o(.text+0x29946):/home/srb/SRB3_4_2/mySRB/src/alpha1.c:12756: undefined reference to `PQfinish' collect2: ld returned 1 exit status gmake: *** [etd.cgi] Error 1