how to get the path with trailing pathseparator in c++ using boost

Question

I have a path such as this:

boost::filesystem::path mypath("c:/test");
boost::filesystem::path mypath1("c:/test/);

I want to make sure that when I convert them to string, both of them appears as :

c:/test/

for example if I do:

cout<<mypath.string()<<endl;
cout<<mypath1.string()<<endl;

both of them print out:

c:/test/

How can I do this in c++ using boost?

I don't think any of the standard functions in the file system library supports what you are after, it will always tread C:/test as a file and C:/test/ as a directory - until you check it.. Your best bet would be to convert to string and check if it ends with a path separator and if not, add it to the string! — Nim
– Nim, Commented Oct 27, 2015 at 14:55

sehe · Accepted Answer · 2015-10-28 09:40:39Z

1

I don't think there is a builtin function.

You could use this, though:

if ("." != p.filename()) 
   p += fs::path::preferred_separator;

This will not add the separator if the path ends in /.

Optionally, call p.remove_trailing_separator first, but that will also remove any trailing double-slash if it was part of the input (some applications treat this as having significant meaning).

Live On Coliru

#include <boost/filesystem.hpp>
#include <boost/range/iterator_range.hpp>
#include <iostream>

namespace fs = boost::filesystem;

int main(int argc, char** argv) {
    for (std::string s : boost::make_iterator_range(argv+1, argv+argc)) {
        fs::path p = s;
        //p.remove_trailing_separator();
        if ("." != p.filename())
            p += fs::path::preferred_separator;

        std::cout << "'" << s << "'\t" << p << "\n";
    }
}

Prints (on linux, obviously):

'.' "."
''  "/"
'/' "//"
'/tmp'  "/tmp/"
'/tmp/' "/tmp/"
'/tmp//'    "/tmp//"
'/tmp/.'    "/tmp/."
'/tmp/..'   "/tmp/../"
'/tmp/...'  "/tmp/.../"
'/tmp/aa.txt'   "/tmp/aa.txt/"
'c:\test.txt'   "c:\test.txt/"

answered Oct 28, 2015 at 9:40

sehe

400k49 gold badges475 silver badges673 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

sercxjo Over a year ago

why you excludes "." but not "" ?

sehe Over a year ago

@sercxjo Actually, I don't remember. I think "" is just a bad example - it's not a valid path and it would be unsafe to assume it means "/". So I'd rather suggest to input validate that "" is not valid input and always leave a trailing /, including "./". To be completely honest, I think the real problem is that it is pretty unclear why the output format matters to OP (to me /some/path/./ doesn't make more sense than /some/path/.. My examples were chosen to reflect how weird the requirement works out, see the last entries)

sehe Over a year ago

@sercxjo Ah. I (and you) should just have tried it out. The comment in the answer explained it: "This will not add the separator if the path ends in /.", compare: coliru.stacked-crooked.com/a/cb04270976fd76f6

Collectives™ on Stack Overflow

how to get the path with trailing pathseparator in c++ using boost

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related