std::filesystem::remove, std::filesystem::remove_all
From cppreference.com
< cpp | filesystem
Defined in header <filesystem>
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||
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).Contents |
[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 |
[edit] See also
erases a file (function) |