std::filesystem::absolute
From cppreference.com
< cpp | filesystem
C++
Feature test macros (C++20)
Concepts library (C++20)
Metaprogramming library (C++11)
Ranges library (C++20)
Filesystem library (C++17)
Concurrency support library (C++11)
Execution control library (C++26)
Filesystem library
filesystem::absolute
Defined in header
<filesystem>
path absolute( const std::filesystem::path & p );
(1)
(since C++17)
path absolute( const std::filesystem::path & p, std::error_code & ec );
(2)
(since C++17)
Returns a path referencing the same file system location as p, for which filesystem::path::is_absolute() is true.
2) This non-throwing overload returns default-constructed path if an error occurs.
[edit] Parameters
p
-
path to convert to absolute form
ec
-
out-parameter for error reporting in the non-throwing overload
[edit] Return value
Returns an absolute (although not necessarily canonical) pathname referencing the same file as p.
[edit] Exceptions
Any overload not marked noexcept may throw std::bad_alloc if memory allocation fails.
1) Throws std::filesystem::filesystem_error on underlying OS API errors, constructed with p as the first path argument and the OS error code as the error code argument.
2) Sets a std::error_code & parameter to the OS API error code if an OS API call fails, and executes ec.clear () if no errors occur.
[edit] Notes
Implementations are encouraged to not consider p not existing to be an error.
For POSIX-based operating systems, std::filesystem::absolute(p) is equivalent to std::filesystem::current_path () / p except for when p is the empty path.
For Windows, std::filesystem::absolute may be implemented as a call to GetFullPathNameW.
[edit] Example
Run this code
#include <filesystem> #include <iostream> namespace fs = std::filesystem; int main() { std::filesystem::path p = "foo.c"; std::cout << "Current path is " << std::filesystem::current_path () << '\n'; std::cout << "Absolute path for " << p << " is " << fs::absolute(p) << '\n'; }
Possible output:
Current path is "/tmp/1666297965.0051296" Absolute path for "foo.c" is "/tmp/1666297965.0051296/foo.c"