PTSNAME(3) Linux Programmer's Manual PTSNAME(3)
NAME
ptsname, ptsname_r - get the name of the slave pseudoterminal
SYNOPSIS
#include <stdlib.h>
char *ptsname(int fd);
int ptsname_r(int fd, char *buf, size_t buflen);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
ptsname():
Since glibc 2.24:
_XOPEN_SOURCE >= 500 ||
(_XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED)
Glibc 2.23 and earlier:
_XOPEN_SOURCE
ptsname_r():
_GNU_SOURCE
DESCRIPTION
The ptsname() function returns the name of the slave pseudoterminal de-
vice corresponding to the master referred to by fd.
The ptsname_r() function is the reentrant equivalent of ptsname(). It
returns the name of the slave pseudoterminal device as a null-termi-
nated string in the buffer pointed to by buf. The buflen argument
specifies the number of bytes available in buf.
RETURN VALUE
On success, ptsname() returns a pointer to a string in static storage
which will be overwritten by subsequent calls. This pointer must not
be freed. On failure, NULL is returned.
On success, ptsname_r() returns 0. On failure, an error number is re-
turned to indicate the error.
ERRORS
EINVAL (ptsname_r() only) buf is NULL. (This error is returned only
for glibc 2.25 and earlier.)
ENOTTY fd does not refer to a pseudoterminal master device.
ERANGE (ptsname_r() only) buf is too small.
VERSIONS
ptsname() is provided in glibc since version 2.1.
ATTRIBUTES
For an explanation of the terms used in this section, see at-
tributes(7).
+------------+---------------+------------------------+
|Interface | Attribute | Value |
+------------+---------------+------------------------+
|ptsname() | Thread safety | MT-Unsafe race:ptsname |
+------------+---------------+------------------------+
|ptsname_r() | Thread safety | MT-Safe |
+------------+---------------+------------------------+
CONFORMING TO
ptsname():
POSIX.1-2001, POSIX.1-2008.
ptsname() is part of the UNIX 98 pseudoterminal support (see pts(4)).
ptsname_r() is a Linux extension, that is proposed for inclusion in the
next major revision of POSIX.1 (Issue 8). A version of this function
is documented on Tru64 and HP-UX, but on those implementations, -1 is
returned on error, with errno set to indicate the error. Avoid using
this function in portable programs.
SEE ALSO
grantpt(3), posix_openpt(3), ttyname(3), unlockpt(3), pts(4), pty(7)
COLOPHON
This page is part of release 5.07 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
2020-06-09 PTSNAME(3)