Files

Safety First

IO operations can fail.
And they will fail!
Either...
- throws std::filesystem::filesystem_error or...
- returns std::error_code as output_parameter

Safety First

Most functions have 2 signatures, one throwing and one noexcept

bool exists( const std::filesystem::path& p );
bool exists( const std::filesystem::path& p,
             std::error_code& ec ) noexcept;

File Information

exists(p)
file_size(p)
is_empty(p), is_regular_file(), ...
links, permissions, mtime, status, ...

Read/Write with

std::fstream(const char*, mode) (since C++98)
std::fstream(std::string const&, mode) (since C++11)
std::fstream(std::filesystem::path const&, mode) (since C++17)

Rename, Copy, Etc..

copy(from, to) - copy file or directory
copy_file(from, to) - copy file only
rename(old_p, new_p)
remove(p), remove_all(p)