xref: /original-bsd/lib/libc/sys/unlink.2 (revision cde01d6c)
1.\" Copyright (c) 1980, 1991 Regents of the University of California.
2.\" All rights reserved.
3.\"
4.\" %sccs.include.redist.man%
5.\"
6.\"     @(#)unlink.2	6.4 (Berkeley) 07/27/92
7.\"
8.Dd
9.Dt UNLINK 2
10.Os BSD 4
11.Sh NAME
12.Nm unlink
13.Nd remove directory entry
14.Sh SYNOPSIS
15.Fd #include <unistd.h>
16.Ft int
17.Fn unlink "const char *path"
18.Sh DESCRIPTION
19The
20.Fn unlink
21function
22removes the link named by
23.Fa path
24from its directory and decrements the link count of the
25file which was referenced by the link.
26If that decrement reduces the link count of the file
27to zero,
28and no process has the file open, then
29all resources associated with the file are reclaimed.
30If one or more process have the file open when the last link is removed,
31the link is removed, but the removal of the file is delayed until
32all references to it have been closed.
33.Sh RETURN VALUES
34Upon successful completion, a value of 0 is returned.
35Otherwise, a value of -1 is returned and
36.Va errno
37is set to indicate the error.
38.Sh ERRORS
39The
40.Fn unlink
41succeeds unless:
42.Bl -tag -width ENAMETOOLONGAA
43.It Bq Er ENOTDIR
44A component of the path prefix is not a directory.
45.It Bq Er EINVAL
46The pathname contains a character with the high-order bit set.
47.It Bq Er ENAMETOOLONG
48A component of a pathname exceeded 255 characters,
49or an entire path name exceeded 1023 characters.
50.It Bq Er ENOENT
51The named file does not exist.
52.It Bq Er EACCES
53Search permission is denied for a component of the path prefix.
54.It Bq Er EACCES
55Write permission is denied on the directory containing the link
56to be removed.
57.It Bq Er ELOOP
58Too many symbolic links were encountered in translating the pathname.
59.It Bq Er EPERM
60The named file is a directory and the effective user ID
61of the process is not the super-user.
62.It Bq Er EPERM
63The directory containing the file is marked sticky,
64and neither the containing directory nor the file to be removed
65are owned by the effective user ID.
66.It Bq Er EBUSY
67The entry to be unlinked is the mount point for a
68mounted file system.
69.It Bq Er EIO
70An I/O error occurred while deleting the directory entry
71or deallocating the inode.
72.It Bq Er EROFS
73The named file resides on a read-only file system.
74.It Bq Er EFAULT
75.Fa Path
76points outside the process's allocated address space.
77.El
78.Sh SEE ALSO
79.Xr close 2 ,
80.Xr link 2 ,
81.Xr rmdir 2
82.Xr symlink 7
83.Sh HISTORY
84An
85.Nm
86function call appeared in Version 6 AT&T UNIX.
87