std::filesystem::file_time_type

 

C++

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Technical specifications

Symbols index

External libraries

 

Filesystem library

Classes
filesystem::path filesystem::filesystem_error filesystem::directory_entry filesystem::directory_iterator filesystem::recursive_directory_iterator      filesystem::file_status	filesystem::space_info filesystem::file_type filesystem::perms filesystem::perm_options filesystem::copy_options filesystem::directory_options filesystem::file_time_type
Functions
filesystem::absolute filesystem::canonicalfilesystem::weakly_canonical filesystem::relativefilesystem::proximate filesystem::copy filesystem::copy_file filesystem::copy_symlink filesystem::create_directory filesystem::create_directories filesystem::create_hard_link filesystem::create_symlink filesystem::create_directory_symlink filesystem::current_path	filesystem::exists filesystem::equivalent filesystem::file_size filesystem::hard_link_count filesystem::last_write_time filesystem::permissions filesystem::read_symlink filesystem::remove filesystem::remove_all filesystem::rename filesystem::resize_file filesystem::space filesystem::status filesystem::symlink_status filesystem::temp_directory_path
File types
filesystem::is_block_file filesystem::is_character_file filesystem::is_directory filesystem::is_empty filesystem::status_known	filesystem::is_fifo filesystem::is_other filesystem::is_regular_file filesystem::is_socket filesystem::is_symlink

 

Defined in header <filesystem>
using file_time_type = std::chrono::time_point</*trivial-clock*/>;		(since C++17) (until C++20)
using file_time_type = std::chrono::time_point<std::chrono::file_clock>;		(since C++20)

Represents file time.

trivial-clock is an implementation-defined type that satisfies TrivialClock and is sufficient to represent the resolution and range of the file time values offered by the filesystem.

(until C++20)

Example

Run this code

#include <chrono>
#include <filesystem>
#include <format>
#include <fstream>
#include <iostream>
 
using namespace std::chrono_literals;
 
int main()
{
    auto p = std::filesystem::temp_directory_path() / "example.bin";
    std::ofstream(p.c_str()).put('a'); // create file
 
    std::filesystem::file_time_type ftime = std::filesystem::last_write_time(p);
    std::cout << std::format("File write time is {}\n", ftime);
 
    std::filesystem::last_write_time(p, ftime + 1h); // move file write time 1 hour to the future
    ftime = std::filesystem::last_write_time(p); // read back from the filesystem
    std::cout << std::format("File write time is {}\n", ftime);
 
    std::filesystem::remove(p);
}

Possible output:

File write time is Sun May  9 23:29:58 2021
File write time is Mon May 10 00:29:58 2021

See also

last_write_time (C++17)

gets or sets the time of the last data modification (function)