The man page for the function will also show which includes are needed - Joe Bogdan Cristea wrote:

Sorry for the previous message, after some google search I have found that with

nm --print-file-name /usr/lib/* 2> /dev/null | grep sem_init

one is able to find what library is needed for a given fct. name.

---------- Forwarded message ---------- From: Bogdan Cristea Date: Thu, Apr 24, 2008 at 11:26 AM Subject: Unable to compile program using POSIX semaphores To: programming@opensuse.org Cc: opensuse@opensuse.org

I use semaphores in a C++ class, but I get errors when linking my programs. Below is the output when compiling and linking the programs. It seems that the functions related to semaphores are not found by the linker. Could you advise please?

g++ -c -ansi -pedantic -Werror -Wall -O3 -W -Wconversion -Wshadow -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings -fshort-enums -fno-common use_cb.cpp -o use_cb.o g++ -c -ansi -pedantic -Werror -Wall -O3 -W -Wconversion -Wshadow -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings -fshort-enums -fno-common CB.cpp -o CB.o g++ use_cb.o CB.o -o use_cb CB.o: In function `CB::reset()': CB.cpp:(.text+0x1e5): undefined reference to `sem_destroy' CB.cpp:(.text+0x200): undefined reference to `sem_init' CB.o: In function `CB::create(int const&)': CB.cpp:(.text+0x266): undefined reference to `sem_init' CB.o: In function `CB::write(char const*, int const&)': CB.cpp:(.text+0x35f): undefined reference to `sem_post' CB.o: In function `CB::read(char*, int const&)': CB.cpp:(.text+0x3e7): undefined reference to `sem_wait' CB.o: In function `CB::clear()': CB.cpp:(.text+0x565): undefined reference to `sem_destroy' CB.cpp:(.text+0x580): undefined reference to `sem_init' CB.o: In function `CB::release()': CB.cpp:(.text+0x5dc): undefined reference to `sem_destroy' CB.cpp:(.text+0x5f7): undefined reference to `sem_init' CB.cpp:(.text+0x62f): undefined reference to `sem_destroy' collect2: ld returned 1 exit status make: *** [use_cb] Error 1 -- Bogdan Cristea

-- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org