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      std::filesystem::create_symlink,std::filesystem::create_directory_symlink

      From cppreference.com
      <cpp‎ |filesystem
       
       
      Filesystem library
      Classes
      Functions
      File types
       
      Defined in header<filesystem>
      void create_symlink(conststd::filesystem::path& target,
                           conststd::filesystem::path& link);
      (1)(since C++17)
      void create_symlink(conststd::filesystem::path& target,

                           conststd::filesystem::path& link,

                           std::error_code& ec)noexcept;
      (2)(since C++17)
      void create_directory_symlink(conststd::filesystem::path& target,
                                     conststd::filesystem::path& link);
      (3)(since C++17)
      void create_directory_symlink(conststd::filesystem::path& target,

                                     conststd::filesystem::path& link,

                                     std::error_code& ec)noexcept;
      (4)(since C++17)

      Creates a symbolic linklink with its target set totarget as if by POSIXsymlink(): the pathnametarget 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.

      Contents

      [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 markednoexcept may throwstd::bad_alloc if memory allocation fails.

      1,3) Throwsstd::filesystem::filesystem_error on underlying OS API errors, constructed withtarget as the first path argument,link as the second path argument, and the OS error code as the error code argument.
      2,4) Sets astd::error_code& parameter to the OS API error code if an OS API call fails, and executesec.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 thetarget argument need not exist when the link is created. A symbolic link can cross file system boundaries.

      [edit]Example

      Run this code
      #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

      (C++17)(C++17)
      determines file attributes
      determines file attributes, checking the symlink target
      (function)[edit]
      obtains the target of a symbolic link
      (function)[edit]
      creates a hard link
      (function)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/filesystem/create_symlink&oldid=157956"

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