std::filesystem::remove, std::filesystem::remove_all

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C++
Filesystem library
Classes
Functions
File types
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
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

Parameters

p - path to delete
ec - out-parameter for error reporting in the non-throwing overload.

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
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 )

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
2,4) Sets a std::error_code& parameter to the OS API error code if an OS API call fails, and executes ec. clear ()

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.

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

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

See also

 erases a file
(function)
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