std::filesystem::read_symlink

 

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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::file_time_type filesystem::perms filesystem::perm_options filesystem::copy_options filesystem::directory_options
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::temp_directory_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
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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>
std::filesystem::path read_symlink(conststd::filesystem::path& p );	(1)	(since C++17)
std::filesystem::path read_symlink(conststd::filesystem::path& p,                                     std::error_code& ec );	(2)	(since C++17)

If the path p refers to a symbolic link, returns a new path object which refers to the target of that symbolic link.

It is an error if p does not refer to a symbolic link.

The non-throwing overload returns an empty path on errors.

Parameters

p	-	path to a symlink
ec	-	out-parameter for error reporting in the non-throwing overload

Return value

The target of the symlink (which may not necessarily exist).

Exceptions

Any overload not marked noexcept may throw std::bad_alloc if memory allocation fails.

1) Throws std::filesystem::filesystem_error on underlying OS API errors, constructed with p as the first path argument and the OS error code as the error code argument.

2) 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.

Example

Run this code

#include <filesystem>#include <iostream>   namespace fs = std::filesystem;   int main(){for(fs::path p :{"/usr/bin/gcc", "/bin/cat", "/bin/mouse"}){std::cout<< p; fs::exists(p)? fs::is_symlink(p)?std::cout<<" -> "<< fs::read_symlink(p)<<'\n':std::cout<<" exists but it is not a symlink\n":std::cout<<" does not exist\n";}}

Possible output:

"/usr/bin/gcc" -> "gcc-5" "/bin/cat" exists but it is not a symlink "/bin/mouse" does not exist

See also

is_symlink (C++17)	checks whether the argument refers to a symbolic link (function)
create_symlinkcreate_directory_symlink (C++17)(C++17)	creates a symbolic link (function)
copy_symlink (C++17)	copies a symbolic link (function)
statussymlink_status (C++17)(C++17)	determines file attributes determines file attributes, checking the symlink target (function)