What methods of the boost::filesystem
library can help me to get a path relative to another path?
I have a path /home/user1/Downloads/Books
and a path /home/user1/
. Now I want to get a path Downloads/Books
.
Taken from a link found by following the ticket Nicol linked to:
template < >
path& path::append< typename path::iterator >( typename path::iterator begin, typename path::iterator end, const codecvt_type& cvt)
{
for( ; begin != end ; ++begin )
*this /= *begin;
return *this;
}
// Return path when appended to a_From will resolve to same as a_To
boost::filesystem::path make_relative( boost::filesystem::path a_From, boost::filesystem::path a_To )
{
a_From = boost::filesystem::absolute( a_From ); a_To = boost::filesystem::absolute( a_To );
boost::filesystem::path ret;
boost::filesystem::path::const_iterator itrFrom( a_From.begin() ), itrTo( a_To.begin() );
// Find common base
for( boost::filesystem::path::const_iterator toEnd( a_To.end() ), fromEnd( a_From.end() ) ; itrFrom != fromEnd && itrTo != toEnd && *itrFrom == *itrTo; ++itrFrom, ++itrTo );
// Navigate backwards in directory to reach previously found base
for( boost::filesystem::path::const_iterator fromEnd( a_From.end() ); itrFrom != fromEnd; ++itrFrom )
{
if( (*itrFrom) != "." )
ret /= "..";
}
// Now navigate down the directory branch
ret.append( itrTo, a_To.end() );
return ret;
}
Stick that in a header file and it should do what you want.
Sample call:
boost::filesystem::path a("foo/bar"), b("foo/test/korv.txt");
std::cout << make_relative( a, b ).string() << std::endl;