Question

I am trying to use an external library called iniparser in my C program. I’m using gcc 4.4.

I put the iniparser library in a subdirectory called lib/ header files are in lib/iniparser/src and the library is compiled to lib/iniparser/libiniparser.so.0.

I wrote a short Makefile to compile it, here’s the output of make:

gcc -Wall -Wextra -Werror -c -I include/ src/smag_main.c -L lib/iniparser -liniparser -I lib/iniparser/src
gcc -Wall -Wextra -Werror -c -I include/ -L lib/iniparser -liniparser -I lib/iniparser/src src/agros.c
gcc -Wall -Wextra -Werror -c -I include/ -L lib/iniparser -liniparser -I lib/iniparser/src src/main.c
gcc -Wall -Wextra -Werror -L lib/iniparser -liniparser -o agros smag_main.o main.o agros.o
smag_main.o: In function `sec_haskey':
smag_main.c:(.text+0xa9): undefined reference to `iniparser_find_entry'
smag_main.o: In function `parse_config':
smag_main.c:(.text+0x153): undefined reference to `iniparser_load'
smag_main.c:(.text+0x18b): undefined reference to `iniparser_getint'
smag_main.c:(.text+0x1c6): undefined reference to `iniparser_getstring'
smag_main.c:(.text+0x202): undefined reference to `iniparser_getstring'
smag_main.c:(.text+0x261): undefined reference to `iniparser_getstring'
smag_main.c:(.text+0x2c2): undefined reference to `iniparser_getint'
smag_main.c:(.text+0x2d5): undefined reference to `iniparser_freedict'
collect2: ld returned 1 exit status
make: *** [agros] Error 1

First call to gcc compiles smag_main.o successfully, the second one compiles agros.o and the third one main.o. The 4th call is the linker, that will link all those objects into an executable agros. It obviously fails.

It looks like it has problems locating iniparser.so at linking time. How’s my call wrong?
I am confused.

(Alternate question, if anyone could explain how to the linking by calling ld directly it would be great).

Answer 1

Try putting a symlink from libiniparser.so.0 to libiniparser.so

 cd lib/iniparser/
 ln -s libiniparser.so.0 libiniparser.so