std::filesystem::directory_entry:: replace_filename

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C++
Filesystem library
Classes
Functions
File types
std::filesystem::directory_entry
Member functions
Modifiers
directory_entry::replace_filename
Observers
(until C++20) (until C++20) (until C++20) (until C++20) (until C++20) (C++20)
Non-member functions
void replace_filename ( const std:: filesystem :: path & p ) ;
(1) (since C++17)
void replace_filename ( const std:: filesystem :: path & p, std:: error_code & ec ) ;
(2) (since C++17)

Changes the filename of the directory entry.

Effectively modifies the path member by path. replace_filename ( p ) and calls refresh to update the cached attributes. If an error occurs, the values of the cached attributes are unspecified.

This function does not commit any changes to the filesystem.

Parameters

p - the path to append to the parent path of the currently stored path
ec - out-parameter for error reporting in the non-throwing overload

Return value

(none)

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.

Example

Run this code 
#include <filesystem>
#include <iostream>
 
int main()
{
    namespace fs = std::filesystem;
    {
        fs::directory_entry entry{"alpha"};
        std::cout << entry << '\n';
        entry.replace_filename("omega");
        std::cout << entry << '\n';
    }
    {
        fs::directory_entry entry{"/alpha/"};
        std::cout << entry << '\n';
        entry.replace_filename("omega");
        std::cout << entry << '\n';
    }
}

Output: 

"alpha"
"omega"
"/alpha/"
"/alpha/omega"

See also

assigns contents
(public member function)
replaces the last path component with another path
(public member function of std::filesystem::path )
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