Greetings All, Thank you so much, Mr. Loskot, for spending your precious time to help a C++ dingbat like me. I followed your instructions to link the libraries, with the "-lboost_filesystem -lboost_system" sequence of linking the aforementioned Boost C++ libraries. However, I cannot resolve the linking error. I have included a snippet from my Terminal session below. Go Bears >make all g++ -L/usr/lib -lboost_filesystem -lboost_system get_sys_info.cpp /tmp/cchfM9Y3.o: In function `__static_initialization_and_destruction_0(int, int)': get_sys_info.cpp:(.text+0x13f): undefined reference to `boost::system::generic_category()' get_sys_info.cpp:(.text+0x14b): undefined reference to `boost::system::generic_category()' get_sys_info.cpp:(.text+0x157): undefined reference to `boost::system::system_category()' /tmp/cchfM9Y3.o: In function `boost::filesystem3::path::codecvt()': get_sys_info.cpp:(.text._ZN5boost11filesystem34path7codecvtEv[boost::filesystem3::path::codecvt()]+0x5): undefined reference to `boost::filesystem3::path::wchar_t_codecvt_facet()' collect2: ld returned 1 exit status make: *** [all] Error 1 Go Bears >make linkerr g++ -t -Wl,--start-group -L/usr/lib -lboost_filesystem -lboost_system get_sys_info.cpp -Wl,--end-group /usr/bin/ld: mode elf_x86_64 /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../x86_64-linux-gnu/crt1.o /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../x86_64-linux-gnu/crti.o /usr/lib/gcc/x86_64-linux-gnu/4.6/crtbegin.o -lboost_filesystem (/usr/lib/libboost_filesystem.so) -lboost_system (/usr/lib/libboost_system.so) /tmp/ccKXKAXo.o -lstdc++ (/usr/lib/gcc/x86_64-linux-gnu/4.6/libstdc++.so) -lm (/usr/lib/gcc/x86_64-linux-gnu/4.6/../../../x86_64-linux-gnu/libm.so) -lgcc_s (/usr/lib/gcc/x86_64-linux-gnu/4.6/libgcc_s.so) /lib/x86_64-linux-gnu/libc.so.6 (/usr/lib/x86_64-linux-gnu/libc_nonshared.a)elf-init.oS /lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 -lgcc_s (/usr/lib/gcc/x86_64-linux-gnu/4.6/libgcc_s.so) /usr/lib/gcc/x86_64-linux-gnu/4.6/crtend.o /usr/lib/gcc/x86_64-linux-gnu/4.6/../../../x86_64-linux-gnu/crtn.o /tmp/ccKXKAXo.o: In function `__static_initialization_and_destruction_0(int, int)': get_sys_info.cpp:(.text+0x13f): undefined reference to `boost::system::generic_category()' get_sys_info.cpp:(.text+0x14b): undefined reference to `boost::system::generic_category()' get_sys_info.cpp:(.text+0x157): undefined reference to `boost::system::system_category()' /tmp/ccKXKAXo.o: In function `boost::filesystem3::path::codecvt()': get_sys_info.cpp:(.text._ZN5boost11filesystem34path7codecvtEv[boost::filesystem3::path::codecvt()]+0x5): undefined reference to `boost::filesystem3::path::wchar_t_codecvt_facet()' /usr/bin/ld: link errors found, deleting executable `a.out' collect2: ld returned 1 exit status make: *** [linkerr] Error 1 Go Bears > The Make targets from my Makefile are: all: g++ -L/usr/lib -lboost_filesystem -lboost_system get_sys_info.cpp ./a.out linkerr: g++ -t -Wl,--start-group -L/usr/lib -lboost_filesystem -lboost_system get_sys_info.cpp -Wl,--end-group ./a.out I had a look at the blog, and used the "-t", "-Wl,--start-group", and "-Wl,--end-group" options to help me "figure" out what is going on. Did I fail to include an appropriate header file in my C++ code, or did I fail to include another Boost C++ Library? How can I tell what is wrong, where did I go wrong, and figure out how can I resolve this? Can you please kindly share your wisdom and insights with me? Thank you very much, and have an awesome day! Regards On Thu, Feb 7, 2013 at 9:53 AM, Mateusz Loskot <mateusz@loskot.net> wrote:
On 7 February 2013 17:08, Giovanni <giovanni.ong@comsoc.org> wrote:
g++ -L/usr/lib -lboost_system get_sys_info.cpp /tmp/cckONUUl.o: In function `__static_initialization_and_destruction_0(int, int)': get_sys_info.cpp:(.text+0x13f): undefined reference to `boost::system::generic_category()' get_sys_info.cpp:(.text+0x14b): undefined reference to `boost::system::generic_category()' get_sys_info.cpp:(.text+0x157): undefined reference to `boost::system::system_category()' /tmp/cckONUUl.o: In function `boost::filesystem3::path::codecvt()': get_sys_info.cpp:(.text._ZN5boost11filesystem34path7codecvtEv[boost::filesystem3::path::codecvt()]+0x5): undefined reference to `boost::filesystem3::path::wchar_t_codecvt_facet()' collect2: ld returned 1 exit status make: *** [all] Error 1
-lboost_filesystem -lboost_system
So, I am back to square one with the "undefined reference" compilation error.
Linking error, you mean.
Can you please kindly suggest how can I resolve this problem? Thank you.
Volodya's blog post may help too
http://vladimir_prus.blogspot.co.uk/2009/06/linking-101.html