std::experi..._directory,(3)

🌸 NAME 🌸 — std::experi..._directory,(3) from the C++ Standard Libary

okay so bestie, you opened the std::experi..._directory,(3) page in the C++ Standard Libary, and the NAME section is exactly this icon:

std::experimental::filesystem::create_directory, - std::experimental::filesystem::create_directory,

That’s the whole name vibe as printed — yes, with the comma and the dash doing their little thing. We’re also covering create_directories because it shows up in the synopsis and it’s part of this whole directory-making moment. 🫶

🔎 SYNOPSIS 🔎

First, the signatures, with the (filesystem TS) labels and overload numbers kept exactly where they were:

Defined in header <experimental/filesystem>
bool create_directory( const path& p );                          (1)
(filesystem TS)
bool create_directory( const path& p, error_code& ec );
bool create_directory( const path& p, const path& existing_p );
bool create_directory( const path& p, const path& existing_p,    (2)
(filesystem TS)
error_code& ec );
bool create_directories( const path& p );                        (3)
(filesystem TS)
bool create_directories( const path& p, error_code& ec );

Then the actual tea:

1) Creates the directory p as if by POSIX mkdir() with a second argument of static_cast<int>(fs::perms::all) (the parent directory must already exist). If p already exists and is already a directory, the function does nothing (this condition is not treated as an error). 💅

2) Same as (1), except that the attributes of the new directory are copied from existing_p (which must be a directory that exists). It is OS-dependent which attributes are copied: on POSIX systems, the attributes are copied as if by

stat(existing_p.c_str(), &attributes_stat)
mkdir(p.c_str(), attributes_stat.st_mode)

On Windows OS, the attributes are copied as if by

CreateDirectoryExW(existing_p.c_str(), p.c_str(), 0)

3) Executes (1) for every element of p that does not already exist.

The non-throwing overloads return false if any error occurs.

🎀 PARAMETERS 🎀

• p — the path to the new directory to create
• existing_p — the path to a directory to copy the attributes from
• ec — out-parameter for error reporting in the non-throwing overload

🦋 RETURN VALUE 🦋

1,2) true if directory creation is successful, false otherwise.

🚨 EXCEPTIONS 🚨

1,3) The overload that does not take an error_code& parameter throws filesystem_error on underlying OS API errors, constructed with p as the first argument and the OS error code as the error code argument. std::bad_alloc may be thrown if memory allocation fails. The overload taking an error_code& parameter sets it to the OS API error code if an OS API call fails, and executes ec.clear() if no errors occur. This overload has noexcept specification: noexcept.

2) The overload that does not take an error_code& parameter throws filesystem_error on underlying OS API errors, constructed with p as the first argument, existing_p as the second argument, and the OS error code as the error code argument. std::bad_alloc may be thrown if memory allocation fails. The overload taking an error_code& parameter sets it to the OS API error code if an OS API call fails, and executes ec.clear() if no errors occur. This overload has noexcept specification: noexcept.

📝 NOTES 📝

The attribute-preserving overload (2) is implicitly invoked by copy() when recursively copying directories. Its equivalent in boost.filesystem is copy_directory (with argument order reversed).

✨ EXAMPLE ✨

// Run this code

#include <cstdlib>
#include <experimental/filesystem>
#include <fstream>
#include <iostream>
namespace fs = std::experimental::filesystem;

int main()
{
    fs::create_directories("sandbox/1/2/a");
    fs::create_directory("sandbox/1/2/b");
    fs::permissions("sandbox/1/2/b", fs::perms::remove_perms |
fs::perms::others_all);
    fs::create_directory("sandbox/1/2/c", "sandbox/1/2/b");
    std::system("ls -l sandbox/1/2");
    fs::remove_all("sandbox");
}

Possible output:

drwxr-xr-x 2 user group 4096 Apr 15 09:33 a
drwxr-x--- 2 user group 4096 Apr 15 09:33 b
drwxr-x--- 2 user group 4096 Apr 15 09:33 c

👀 SEE ALSO 👀

• create_symlink — creates a symbolic link
• create_directory_symlink — (function)
• copy — copies files or directories (function)
• perms — identifies file system permissions (enum)

🏷️ CATEGORIES 🏷️

• Noindexed pages
• unconditionally noexcept

🙈 HIDDEN CATEGORIES 🙈

• Pages with unreviewed unconditional noexcept template
• Pages with unreviewed noexcept template

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And that’s the vibe check, bestie: this page came from http://cppreference.com, dated 2024.06.10, and the footer name is std::experi..._directory,(3). Slay the filesystem responsibly! 💖✨🎀