xref: /freebsd/lib/libsys/fhreadlink.2 (revision 87b759f0fa1f7554d50ce640c40138512bbded44)
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26.Dd November 30, 2022
27.Dt FHREADLINK 2
28.Os
29.Sh NAME
30.Nm fhreadlink
31.Nd read value of a symbolic link
32.Sh LIBRARY
33.Lb libc
34.Sh SYNOPSIS
35.In sys/param.h
36.In sys/mount.h
37.Ft int
38.Fn fhreadlink "fhandle_t *fhp" "char *buf" "size_t bufsize"
39.Sh DESCRIPTION
40The
41.Fn fhreadlink
42system call
43places the contents of the symbolic link
44.Fa fhp
45in the buffer
46.Fa buf ,
47which has size
48.Fa bufsiz .
49The
50.Fn fhreadlink
51system call does not append a
52.Dv NUL
53character to
54.Fa buf .
55.Pp
56.Sh RETURN VALUES
57The call returns the count of characters placed in the buffer
58if it succeeds, or a \-1 if an error occurs, placing the error
59code in the global variable
60.Va errno .
61.Sh ERRORS
62The
63.Fn readlink
64system call
65will fail if:
66.Bl -tag -width Er
67.It Bq Er ENOENT
68The named file does not exist.
69.It Bq Er ELOOP
70Too many symbolic links were encountered in translating the file handle
71.Fa fhp .
72.It Bq Er EINVAL
73The named file is not a symbolic link.
74.It Bq Er EIO
75An I/O error occurred while reading from the file system.
76.It Bq Er EINTEGRITY
77Corrupted data was detected while reading from the file system.
78.It Bq Er EFAULT
79The
80.Fa buf
81argument
82extends outside the process's allocated address space.
83.It Bq Er ESTALE
84The file handle
85.Fa fhp
86is no longer valid
87.El
88.Sh SEE ALSO
89.Xr fhstat 2 ,
90.Xr fhlink 2 ,
91.Sh HISTORY
92The
93.Fn fhreadlink
94system call first appeared in
95.Fx 12.1 .
96