std::filesystem::remove, std::filesystem::remove_all
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< 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)
Defined in header
<filesystem>
bool remove( const std::filesystem::path & p );
(1)
(since C++17)
bool remove( const std::filesystem::path & p, std::error_code & ec ) noexcept;
(2)
(since C++17)
std::uintmax_t remove_all( const std::filesystem::path & p );
(3)
(since C++17)
std::uintmax_t remove_all( const std::filesystem::path & p, std::error_code & ec );
(4)
(since C++17)
1,2) The file or empty directory identified by the path p is deleted as if by the POSIX
remove. Symlinks are not followed (symlink is removed, not its target).3,4) Deletes the contents of p (if it is a directory) and the contents of all its subdirectories, recursively, then deletes p itself as if by repeatedly applying the POSIX
remove. Symlinks are not followed (symlink is removed, not its target).[edit] Parameters
p
-
path to delete
ec
-
out-parameter for error reporting in the non-throwing overload.
[edit] Return value
1,2) true if the file was deleted, false if it did not exist. The overload that takes
error_code& argument returns false on errors.3,4) Returns the number of files and directories that were deleted (which may be zero if p did not exist to begin with). The overload that takes
error_code& argument returns static_cast<std::uintmax_t >(-1) on error.[edit] Exceptions
Any overload not marked noexcept may throw std::bad_alloc if memory allocation fails.
1,3) 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.
2,4) 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
On POSIX systems, this function typically calls unlink and rmdir as needed, on Windows DeleteFileW and RemoveDirectoryW.
If p did not exist, this function returns false and does not report an error.
[edit] Example
Run this code
#include <cstdint> #include <filesystem> #include <fstream> #include <iostream> int main() { namespace fs = std::filesystem; std::cout << std::boolalpha ; fs::path tmp{std::filesystem::temp_directory_path ()}; const auto O_O{"O_O"}; std::ofstream {tmp / O_O} << O_O; // creates file containing O_O std::cout << "remove(): " << fs::remove(tmp / O_O) << '\n'; // success std::cout << "remove(): " << fs::remove(tmp / O_O) << '\n'; // fail std::filesystem::create_directories (tmp / "abcdef/example"); const std::uintmax_t n{fs::remove_all(tmp / "abcdef")}; std::cout << "remove_all(): " << n << " files or directories\n"; }
Possible output:
remove(): true remove(): false remove_all(): 2 files or directories
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 3014 | C++17 | error_code overload of remove_all marked noexcept but can allocate memory
|
noexcept removed |