Program demonstrating cpp-netlib hang

hang.cpp

#include <string>
#include <boost/network/protocol/http/client.hpp>

std::string download_file(const std::string& url)
{
    using namespace boost::network;
    using namespace boost::network::http;
    client c;
    client::request r{url};
    auto response = c.get(r);
    std::string result = body(response);
    return result;
}

std::string files[] =
{
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ana.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ana.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ant.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ant.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/asabs.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/asabs.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/asdn.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/asdn.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/asi.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/asi.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/assem.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/assem.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ast.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ast.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/bch.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/bch.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ceres.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ceres.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/chm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/chm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/cine.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/cine.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/cita.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/cita.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/clas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/clas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/col.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/col.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/compg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/compg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/crim.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/crim.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/csb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/csb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/csc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/csc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/csus.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/csus.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ctep.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ctep.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/drama.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/drama.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/dts.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/dts.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eco.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eco.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eeb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eeb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eng.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/eng.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/envmt.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/envmt.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/es.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/es.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ethic.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ethic.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/far.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/far.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/for.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/for.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/fre.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/fre.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ger.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ger.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ggr.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ggr.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/glaf.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/glaf.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/his.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/his.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/hmb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/hmb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ihpst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ihpst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/imm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/imm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/innis.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/innis.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ire.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ire.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ita.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/ita.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/jsp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/jsp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/las.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/las.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/lin.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/lin.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/lmp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/lmp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/mat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/mat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/medgm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/medgm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/music.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/music.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/new.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/new.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/nmc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/nmc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/nusci.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/nusci.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/online.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/online.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/otc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/otc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/pcl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/pcl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/phl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/phl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/phm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/phm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/phy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/phy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/pol.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/pol.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/psl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/psl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/psy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/psy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/rlg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/rlg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/sas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/sas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/sdst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/sdst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/sla.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/sla.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/smc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/smc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/soc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/soc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/spa.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/spa.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/spp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/spp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/stat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/stat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/trin.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/trin.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/uc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/uc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/vic.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/vic.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/wdw.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/wdw.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/wgsi.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/winter/wgsi.html",
    "http://www.apsc.utoronto.ca/timetable/fall.html",
    "http://www.apsc.utoronto.ca/timetable/winter.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ana.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ana.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ant.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ant.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/asabs.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/asabs.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ast.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ast.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/bch.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/bch.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/chm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/chm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/cine.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/cine.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/clas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/clas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/compg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/compg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/crim.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/crim.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/csb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/csb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/csc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/csc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/drama.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/drama.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/dts.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/dts.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eas.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eco.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eco.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eeb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eeb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eng.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/eng.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/envmt.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/envmt.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/es.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/es.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/far.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/far.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/for.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/for.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/fre.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/fre.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ger.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ger.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ggr.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ggr.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/his.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/his.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/hmb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/hmb.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ihpst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ihpst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ire.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ire.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ita.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/ita.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/jsp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/jsp.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/lin.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/lin.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/mat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/mat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/music.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/music.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/new.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/new.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/nmc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/nmc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/nusci.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/nusci.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/otc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/otc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/pcl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/pcl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/phl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/phl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/phm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/phm.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/phy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/phy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/pol.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/pol.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/psl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/psl.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/psy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/psy.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/rlg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/rlg.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/sdst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/sdst.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/smc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/smc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/soc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/soc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/spa.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/spa.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/stat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/stat.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/uc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/uc.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/wdw.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/wdw.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/wgsi.html",
    "http://www.artsandscience.utoronto.ca/ofr/timetable/summer/wgsi.html",
};

int main()
{
    for (const std::string& file : files)
        download_file(file);
}