SymLink

Create a symbolic link

Declaration

Source position: oldlinux.pp line 1390

Description

SymLink makes Newpath point to the file in OldPath, which doesn't necessarily exist. The two files DO NOT have the same inode number. This is known as a 'soft' link.

The permissions of the link are irrelevant, as they are not used when following the link. Ownership of the file is only checked in case of removal or renaming of the link.

The function returns True if the call was succesfull, False if the call failed.

Errors

Errors are returned in LinuxError.

sys_eperm

The filesystem containing oldpath and newpath does not support linking files.

sys_eaccess

Write access for the directory containing Newpath is disallowed, or one of the directories in OldPath or NewPath has no search (=execute) permission.

sys_enoent

A directory entry in OldPath or NewPath does not exist or is a symbolic link pointing to a non-existent directory.

sys_enotdir

A directory entry in OldPath or NewPath is nor a directory.

sys_enomem

Insufficient kernel memory.

sys_erofs

The files are on a read-only filesystem.

sys_eexist

NewPath already exists.

sys_eloop

OldPath or NewPath has a reference to a circular symbolic link, i.e. a symbolic link, whose expansion points to itself.

sys_enospc

The device containing NewPath has no room for another entry.

See also

Example

Program Example22;

{ Program to demonstrate the SymLink and UnLink functions. }

Uses oldlinux;

Var F : Text;
    S : String;

begin
  Assign (F,'test.txt');
  Rewrite (F);
  Writeln (F,'This is written to test.txt');
  Close(f);
  { new.txt and test.txt are now the same file }
  if not SymLink ('test.txt','new.txt') then
    writeln ('Error when symlinking !');
  { Removing test.txt still leaves new.txt
    Pointing now to a non-existent file ! }
  If not Unlink ('test.txt') then
    Writeln ('Error when unlinking !');
  Assign (f,'new.txt');
  { This should fail, since the symbolic link
    points to a non-existent file! }
  {$i-}
  Reset (F);
  {$i+}
  If IOResult=0 then
    Writeln ('This shouldn''t happen');
 { Now remove new.txt also }
 If not Unlink ('new.txt') then
   Writeln ('Error when unlinking !');
end.