std::filesystem::create_symlink, std::filesystem::create_directory_symlink
Defined in header <filesystem>
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void create_symlink(
const
std::filesystem::path
& target,
const std::filesystem::path & link ) ; |
(1) | (since C++17) |
void create_symlink(
const
std::filesystem::path
& target,
const std::filesystem::path& link, |
(2) | (since C++17) |
void create_directory_symlink(
const
std::filesystem::path
& target,
const std::filesystem::path & link ) ; |
(3) | (since C++17) |
void create_directory_symlink(
const
std::filesystem::path
& target,
const
std::filesystem::path
& link, |
(4) | (since C++17) |
Creates a symbolic link link with its target set to target as if by POSIX symlink()
: the pathname target
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)
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 |
Return value
(none)
Exceptions
Any overload not marked noexcept
may throw std::bad_alloc if memory allocation fails.
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
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"
See also
(C++17)(C++17)
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determines file attributes determines file attributes, checking the symlink target (function) |
(C++17)
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obtains the target of a symbolic link (function) |
(C++17)
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creates a hard link (function) |