Question

I’m having trouble building a simple c++ program that tests out regex’s from the boost library. The problem that I’m having is occurring in the linking stage and I don’t know enough to fix the error on my own.

In the .cpp program that uses regexes I used the following include line.

#include <boost/regex.hpp>

I don’t know enough to figure out what command I should use to build the program using g++. I tried using the following command line (and variations of it) to build the program.

g++ -I/usr/include/regex -L/usr/lib -llibboost_regex main.cpp -o regex_test

Other information that might be relevant:

Operating system: Arch linux
g++ version: 4.6.2 20120120 (prerelease)

Any help would be appreciated.

Answer 1

Assume you have installed Boost with the boost and boost-libs packages,

1. The header <boost/regex.hpp> should exist in /usr/include/boost/regex.hpp. You don’t need to use any -I flags since /usr/include should be included by default.
2. You shouldn’t need the -L flag either since /usr/lib should also be included by default when linking.
3. When using the -l flag to link with a library libfoo.so, the leading “lib” part should be removed.

The command line should therefore be:

g++ main.cpp -o regex_test -lboost_regex