RetroSearch Browse

Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from http://en.cppreference.com/w/cpp/algorithm/../symbol_index/../filesystem/create_symlink.html below:

std::filesystem::create_symlink, std::filesystem::create_directory_symlink - cppreference.com

Creates a symbolic link link with its target set to target as if by POSIX symlink(): the pathname target may be invalid or non-existing.

Some operating systems require symlink creation to identify that the link is to a directory. Portable code should use (3,4) to create directory symlinks rather than (1,2), even though there is no distinction on POSIX systems.

[edit] Parameters target - path to point the symlink to, does not have to exist link - path of the new symbolic link ec - out-parameter for error reporting in the non-throwing overload [edit] Return value

(none)

[edit] 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

target

as the first path argument,

link

as the second path argument, and the OS error code as the error code argument.

2,4)

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.

[edit] Notes

Some operating systems do not support symbolic links at all or support them only for regular files.

Some file systems do not support symbolic links regardless of the operating system, for example the FAT system used on some memory cards and flash drives.

Like a hard link, a symbolic link allows a file to have multiple logical names. The presence of a hard link guarantees the existence of a file, even after the original name has been removed. A symbolic link provides no such assurance; in fact, the file named by the target argument need not exist when the link is created. A symbolic link can cross file system boundaries.

[edit] Example

#include <cassert>
#include <filesystem>
#include <iostream>
namespace fs = std::filesystem;
 
int main()
{
    fs::create_directories("sandbox/subdir");
    fs::create_symlink("target", "sandbox/sym1");
    fs::create_directory_symlink("subdir", "sandbox/sym2");
 
    for (auto it = fs::directory_iterator("sandbox"); it != fs::directory_iterator(); ++it)
        if (is_symlink(it->symlink_status()))
            std::cout << *it << "->" << read_symlink(*it) << '\n';
 
    assert(std::filesystem::equivalent("sandbox/sym2", "sandbox/subdir"));
    fs::remove_all("sandbox");
}

Possible output:

"sandbox/sym1"->"target"
"sandbox/sym2"->"subdir"

[edit] See also

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4