xref: /netbsd/lib/libc/sys/readlink.2 (revision bf9ec67e)
1.\"	$NetBSD: readlink.2,v 1.15 2002/02/08 01:28:21 ross Exp $
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34.\"     @(#)readlink.2	8.1 (Berkeley) 6/4/93
35.\"
36.Dd June 4, 1993
37.Dt READLINK 2
38.Os
39.Sh NAME
40.Nm readlink
41.Nd read value of a symbolic link
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.Fd #include \*[Lt]unistd.h\*[Gt]
46.Ft int
47.Fn readlink "const char *path" "char *buf" "size_t bufsiz"
48.Sh DESCRIPTION
49.Fn readlink
50places the contents of the symbolic link
51.Fa path
52in the buffer
53.Fa buf ,
54which has size
55.Fa bufsiz .
56.Fn readlink
57does not append a
58.Dv NUL
59character to
60.Fa buf .
61.Sh RETURN VALUES
62The call returns the count of characters placed in the buffer
63if it succeeds, or a -1 if an error occurs, placing the error
64code in the global variable
65.Va errno .
66.Sh ERRORS
67.Fn readlink
68will fail if:
69.Bl -tag -width Er
70.It Bq Er ENOTDIR
71A component of the path prefix is not a directory.
72.It Bq Er ENAMETOOLONG
73A component of a pathname exceeded
74.Dv {NAME_MAX}
75characters, or an entire path name exceeded
76.Dv {PATH_MAX}
77characters.
78.It Bq Er ENOENT
79The named file does not exist.
80.It Bq Er EACCES
81Search permission is denied for a component of the path prefix.
82.It Bq Er ELOOP
83Too many symbolic links were encountered in translating the pathname.
84.It Bq Er EINVAL
85The named file is not a symbolic link.
86.It Bq Er EIO
87An I/O error occurred while reading from the file system.
88.It Bq Er EFAULT
89.Fa buf
90extends outside the process's allocated address space.
91.El
92.Sh SEE ALSO
93.Xr lstat 2 ,
94.Xr stat 2 ,
95.Xr symlink 2 ,
96.Xr symlink 7
97.Sh HISTORY
98The
99.Fn readlink
100function call appeared in
101.Bx 4.2 .
102