std::experimental::filesystem::canonical
From cppreference.com
< cpp | experimental | fs
C++
Experimental
| Technical Specification | ||||
| Filesystem library (filesystem TS) | ||||
| Library fundamentals (library fundamentals TS) | ||||
| Library fundamentals 2 (library fundamentals TS v2) | ||||
| Library fundamentals 3 (library fundamentals TS v3) | ||||
| Extensions for parallelism (parallelism TS) | ||||
| Extensions for parallelism 2 (parallelism TS v2) | ||||
| Extensions for concurrency (concurrency TS) | ||||
| Extensions for concurrency 2 (concurrency TS v2) | ||||
| Concepts (concepts TS) | ||||
| Ranges (ranges TS) | ||||
| Reflection (reflection TS) | ||||
| Mathematical special functions (special functions TR) | ||||
| Experimental Non-TS | ||||
| Pattern Matching | ||||
| Linear Algebra | ||||
| std::execution | ||||
| Contracts | ||||
| 2D Graphics |
Filesystem library
| Classes | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Functions | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| File types | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Defined in header <experimental/filesystem>
|
||
| path canonical( const path& p, const path& base = current_path() ); |
(1) | (filesystem TS) |
| path canonical( const path& p, error_code& ec ); |
(2) | (filesystem TS) |
| path canonical( const path& p, const path& base, error_code& ec ); |
(3) | (filesystem TS) |
Converts path p to a canonical absolute path, i.e. an absolute path that has no dot, dot-dot elements or symbolic links.
If p is not an absolute path, the function behaves as if it is first made absolute by absolute(p, base) or absolute(p) for (2).
The path p must exist.
Contents |
[edit] Parameters
| p | - | a path which may be absolute or relative to base, and which must be an existing path |
| base | - | base path to be used in case p is relative |
| ec | - | error code to store error status to |
[edit] Return value
An absolute path that resolves to the same file as absolute(p, base) (or absolute(p) for (2)).
[edit] Exceptions
The overload that does not take an error_code& parameter throws filesystem_error on underlying OS API errors, constructed with p as the first argument, base as the second argument, and the OS error code as the error code argument. std::bad_alloc may be thrown if memory allocation fails. The overload taking an error_code& parameter sets it to the OS API error code if an OS API call fails, and executes ec.clear() if no errors occur. This overload hasnoexcept specification:
noexcept
This function is modeled after the POSIX realpath.
[edit] Example
Run this code
#include <experimental/filesystem> #include <iostream> namespace fs = std::experimental::filesystem; int main() { fs::path p = fs::path("..") / ".." / "AppData"; std::cout << "Current path is " << fs::current_path() << '\n' << "Canonical path for " << p << " is " << fs::canonical(p) << '\n'; }
Possible output:
Current path is "C:\Users\abcdef\AppData\Local\Temp" Canonical path for "..\..\AppData" is "C:\Users\abcdef\AppData"
[edit] See also
| represents a path (class) [edit] | |
| composes an absolute path converts a path to an absolute path replicating OS-specific behavior (function) [edit] |
