xref: /netbsd-src/lib/libc/sys/unlink.2 (revision 5f7096188587a2c7c95fa3c69b78e1ec9c7923d0)
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32.\"     from: @(#)unlink.2	6.3 (Berkeley) 3/10/91
33.\"	$Id: unlink.2,v 1.3 1993/11/25 00:40:00 jtc Exp $
34.\"
35.Dd March 10, 1991
36.Dt UNLINK 2
37.Os BSD 4
38.Sh NAME
39.Nm unlink
40.Nd remove directory entry
41.Sh SYNOPSIS
42.Fd #include <unistd.h>
43.Ft int
44.Fn unlink "const char *path"
45.Sh DESCRIPTION
46The
47.Fn unlink
48function
49removes the link named by
50.Fa path
51from its directory and decrements the link count of the
52file which was referenced by the link.
53If that decrement reduces the link count of the file
54to zero,
55and no process has the file open, then
56all resources associated with the file are reclaimed.
57If one or more process have the file open when the last link is removed,
58the link is removed, but the removal of the file is delayed until
59all references to it have been closed.
60.Sh RETURN VALUES
61Upon successful completion, a value of 0 is returned.
62Otherwise, a value of -1 is returned and
63.Va errno
64is set to indicate the error.
65.Sh ERRORS
66The
67.Fn unlink
68succeeds unless:
69.Bl -tag -width ENAMETOOLONGAA
70.It Bq Er ENOTDIR
71A component of the path prefix is not a directory.
72.It Bq Er EINVAL
73The pathname contains a character with the high-order bit set.
74.It Bq Er ENAMETOOLONG
75A component of a pathname exceeded 255 characters,
76or an entire path name exceeded 1023 characters.
77.It Bq Er ENOENT
78The named file does not exist.
79.It Bq Er EACCES
80Search permission is denied for a component of the path prefix.
81.It Bq Er EACCES
82Write permission is denied on the directory containing the link
83to be removed.
84.It Bq Er ELOOP
85Too many symbolic links were encountered in translating the pathname.
86.It Bq Er EPERM
87The named file is a directory and the effective user ID
88of the process is not the super-user.
89.It Bq Er EPERM
90The directory containing the file is marked sticky,
91and neither the containing directory nor the file to be removed
92are owned by the effective user ID.
93.It Bq Er EBUSY
94The entry to be unlinked is the mount point for a
95mounted file system.
96.It Bq Er EIO
97An I/O error occurred while deleting the directory entry
98or deallocating the inode.
99.It Bq Er EROFS
100The named file resides on a read-only file system.
101.It Bq Er EFAULT
102.Fa Path
103points outside the process's allocated address space.
104.El
105.Sh SEE ALSO
106.Xr close 2 ,
107.Xr link 2 ,
108.Xr rmdir 2
109.Sh HISTORY
110An
111.Fn unlink
112function call appeared in
113.At v6 .
114