xref: /openbsd/lib/libc/sys/readlink.2 (revision b4ba3a3e)
1.\"	$NetBSD: readlink.2,v 1.7 1995/02/27 12:35:54 cgd 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 BSD 4.2
39.Sh NAME
40.Nm readlink
41.Nd read value of a symbolic link
42.Sh SYNOPSIS
43.Fd #include <unistd.h>
44.Ft int
45.Fn readlink "const char *path" "char *buf" "size_t bufsiz"
46.Sh DESCRIPTION
47.Fn readlink
48places the contents of the symbolic link
49.Fa path
50in the buffer
51.Fa buf ,
52which has size
53.Fa bufsiz .
54.Nm readlink
55does not append a
56.Dv NUL
57character to
58.Fa buf .
59.Sh RETURN VALUES
60The call returns the count of characters placed in the buffer
61if it succeeds, or a -1 if an error occurs, placing the error
62code in the global variable
63.Va errno .
64.Sh ERRORS
65.Fn readlink
66will fail if:
67.Bl -tag -width Er
68.It Bq Er ENOTDIR
69A component of the path prefix is not a directory.
70.It Bq Er ENAMETOOLONG
71A component of a pathname exceeded
72.Dv {NAME_MAX}
73characters, or an entire path name exceeded
74.Dv {PATH_MAX}
75characters.
76.It Bq Er ENOENT
77The named file does not exist.
78.It Bq Er EACCES
79Search permission is denied for a component of the path prefix.
80.It Bq Er ELOOP
81Too many symbolic links were encountered in translating the pathname.
82.It Bq Er EINVAL
83The named file is not a symbolic link.
84.It Bq Er EIO
85An I/O error occurred while reading from the file system.
86.It Bq Er EFAULT
87.Fa Buf
88extends outside the process's allocated address space.
89.El
90.Sh SEE ALSO
91.Xr stat 2 ,
92.Xr lstat 2 ,
93.Xr symlink 2 ,
94.Xr symlink 7
95.Sh HISTORY
96The
97.Fn readlink
98function call appeared in
99.Bx 4.2 .
100