1ptsname(3)                 Library Functions Manual                 ptsname(3)
2
3
4

NAME

6       ptsname, ptsname_r - get the name of the slave pseudoterminal
7

LIBRARY

9       Standard C library (libc, -lc)
10

SYNOPSIS

12       #include <stdlib.h>
13
14       char *ptsname(int fd);
15       int ptsname_r(int fd, char buf[.buflen], size_t buflen);
16
17   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
18
19       ptsname():
20           Since glibc 2.24:
21               _XOPEN_SOURCE >= 500
22           glibc 2.23 and earlier:
23               _XOPEN_SOURCE
24
25       ptsname_r():
26           _GNU_SOURCE
27

DESCRIPTION

29       The ptsname() function returns the name of the slave pseudoterminal de‐
30       vice corresponding to the master referred to by the file descriptor fd.
31
32       The ptsname_r() function is the reentrant equivalent of ptsname().   It
33       returns  the  name  of the slave pseudoterminal device as a null-termi‐
34       nated string in the buffer pointed to  by  buf.   The  buflen  argument
35       specifies the number of bytes available in buf.
36

RETURN VALUE

38       On  success,  ptsname() returns a pointer to a string in static storage
39       which will be overwritten by subsequent calls.  This pointer  must  not
40       be freed.  On failure, NULL is returned.
41
42       On  success, ptsname_r() returns 0.  On failure, an error number is re‐
43       turned to indicate the error.
44

ERRORS

46       EINVAL (ptsname_r() only) buf is NULL.  (This error  is  returned  only
47              for glibc 2.25 and earlier.)
48
49       ENOTTY fd does not refer to a pseudoterminal master device.
50
51       ERANGE (ptsname_r() only) buf is too small.
52

ATTRIBUTES

54       For  an  explanation  of  the  terms  used  in  this  section,  see at‐
55       tributes(7).
56
57       ┌─────────────────────────────┬───────────────┬────────────────────────┐
58Interface                    Attribute     Value                  
59       ├─────────────────────────────┼───────────────┼────────────────────────┤
60ptsname()                    │ Thread safety │ MT-Unsafe race:ptsname │
61       ├─────────────────────────────┼───────────────┼────────────────────────┤
62ptsname_r()                  │ Thread safety │ MT-Safe                │
63       └─────────────────────────────┴───────────────┴────────────────────────┘
64

VERSIONS

66       A version of ptsname_r() is documented on Tru64 and HP-UX, but on those
67       implementations,  -1  is  returned on error, with errno set to indicate
68       the error.  Avoid using this function in portable programs.
69

STANDARDS

71       ptsname():
72              POSIX.1-2008.
73
74       ptsname_r() is a Linux extension, that is proposed for inclusion in the
75       next major revision of POSIX.1 (Issue 8).
76

HISTORY

78       ptsname():
79              POSIX.1-2001.  glibc 2.1.
80
81       ptsname() is part of the UNIX 98 pseudoterminal support (see pts(4)).
82

SEE ALSO

84       grantpt(3), posix_openpt(3), ttyname(3), unlockpt(3), pts(4), pty(7)
85
86
87
88Linux man-pages 6.05              2023-07-20                        ptsname(3)
Impressum