xref: /freebsd-14.2/lib/libc/sys/readlink.2 (revision fffcbbcd)
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32.\"     @(#)readlink.2	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD$
34.\"
35.Dd June 4, 1993
36.Dt READLINK 2
37.Os
38.Sh NAME
39.Nm readlink
40.Nd read value of a symbolic link
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.Fd #include <unistd.h>
45.Ft int
46.Fn readlink "const char *path" "char *buf" "int bufsiz"
47.Sh DESCRIPTION
48.Fn Readlink
49places the contents of the symbolic link
50.Fa path
51in the buffer
52.Fa buf ,
53which has size
54.Fa bufsiz .
55The
56.Fn readlink
57function does 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 255 characters,
74or an entire path name exceeded 1023 characters.
75.It Bq Er ENOENT
76The named file does not exist.
77.It Bq Er EACCES
78Search permission is denied for a component of the path prefix.
79.It Bq Er ELOOP
80Too many symbolic links were encountered in translating the pathname.
81.It Bq Er EINVAL
82The named file is not a symbolic link.
83.It Bq Er EIO
84An I/O error occurred while reading from the file system.
85.It Bq Er EFAULT
86.Fa Buf
87extends outside the process's allocated address space.
88.El
89.Sh SEE ALSO
90.Xr lstat 2 ,
91.Xr stat 2 ,
92.Xr symlink 2 ,
93.Xr symlink 7
94.Sh HISTORY
95The
96.Fn readlink
97function call appeared in
98.Bx 4.2 .
99