Unlink (Unix)

This article is about the Unix system call. For the mathematical concept, see unlink.

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]

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]

Examples

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

• List of Unix commands
• link (Unix)
• ln (Unix)

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.