[fs.op.relative]

# 31 Input/output library [[input.output]](./#input.output)

## 31.12 File systems [[filesystems]](filesystems#fs.op.relative)

### 31.12.13 Filesystem operation functions [[fs.op.funcs]](fs.op.funcs#fs.op.relative)

#### 31.12.13.30 Relative [fs.op.relative]

[🔗](#lib:relative)

`path filesystem::relative(const path& p, error_code& ec);
`

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L18397)

*Returns*: relative(p, current_path(), ec)[.](#1.sentence-1)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L18401)

*Throws*: As specified in [[fs.err.report]](fs.err.report "31.12.5 Error reporting")[.](#2.sentence-1)

[🔗](#lib:relative_)

`path filesystem::relative(const path& p, const path& base = current_path());
path filesystem::relative(const path& p, const path& base, error_code& ec);
`

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L18413)

*Returns*: For the first form:weakly_canonical(p).lexically_relative(weakly_canonical(base));

For the second form:weakly_canonical(p, ec).lexically_relative(weakly_canonical(base, ec)); or path() at the first error occurrence, if any[.](#3.sentence-2)

[4](#4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/iostreams.tex#L18425)

*Throws*: As specified in [[fs.err.report]](fs.err.report "31.12.5 Error reporting")[.](#4.sentence-1)