Unlink (Unix)

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unlink
Operating system Unix and Unix-like
Platform Cross-platform
Type Command

In Unix-like operating systems, unlink is a system call and a command line utility to delete files. The program directly interfaces the system call, which removes the file name and (but not on GNU systems) directories like rm and rmdir. [1] If the file name was the last hard link to the file, the file itself is deleted as soon as no program has it open. [2]

Contents

It also appears in the PHP, Node.js, R, Perl and Python standard libraries in the form of the unlink() built-in function. Like the Unix utility, it is also used to delete files. [3] [4] [5] [6]

Example

To delete a file named foo, one could type:

% unlink foo

In PHP, one could use the following function to do the same:

unlink("foo");

The Perl syntax is identical to the PHP syntax, save for the parentheses:

unlink"foo";

In Node.js it is almost the same as the others:

fs.unlink("foo",callback);

In R (with the S language compatibility):

unlink("foo")#Comment: using the inside argument 'recursive = TRUE', directories can be deleted

Similarly in Python:

os.unlink("foo")

See also

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References

  1. ↑ "GNU Coreutils: unlink invocation". www.gnu.org.
  2. ↑ "unlink". pubs.opengroup.org.
  3. ↑ "PHP: unlink - Manual". php.net.
  4. ↑ "unlink - perldoc.perl.org". perldoc.perl.org.
  5. ↑ "File System - Node.js v13.0.1 Documentation". nodejs.org.
  6. ↑ "os — Miscellaneous operating system interfaces — Python 3.8.0 documentation". python.org.
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