mirror of https://github.com/mkerrisk/man-pages
133 lines
3.0 KiB
Groff
133 lines
3.0 KiB
Groff
.\" %%%LICENSE_START(PUBLIC_DOMAIN)
|
|
.\" This page is in the public domain. - aeb
|
|
.\" %%%LICENSE_END
|
|
.\"
|
|
.\" 2004-12-17, mtk, added description of ptsname_r() + ERRORS
|
|
.\"
|
|
.TH PTSNAME 3 2020-06-09 "" "Linux Programmer's Manual"
|
|
.SH NAME
|
|
ptsname, ptsname_r \- get the name of the slave pseudoterminal
|
|
.SH SYNOPSIS
|
|
.B #include <stdlib.h>
|
|
.PP
|
|
.BI "char *ptsname(int " fd ");"
|
|
.br
|
|
.BI "int ptsname_r(int " fd ", char *" buf ", size_t " buflen ");"
|
|
.PP
|
|
.in -4n
|
|
Feature Test Macro Requirements for glibc (see
|
|
.BR feature_test_macros (7)):
|
|
.in
|
|
.PP
|
|
.ad l
|
|
.BR ptsname ():
|
|
.br
|
|
.RS 4
|
|
Since glibc 2.24:
|
|
_XOPEN_SOURCE\ >=\ 500 ||
|
|
(_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED)
|
|
.br
|
|
Glibc 2.23 and earlier:
|
|
_XOPEN_SOURCE
|
|
.RE
|
|
.PP
|
|
.BR ptsname_r ():
|
|
_GNU_SOURCE
|
|
.ad
|
|
.SH DESCRIPTION
|
|
The
|
|
.BR ptsname ()
|
|
function returns the name of the slave pseudoterminal device
|
|
corresponding to the master referred to by the file descriptor
|
|
.IR fd .
|
|
.PP
|
|
The
|
|
.BR ptsname_r ()
|
|
function is the reentrant equivalent of
|
|
.BR ptsname ().
|
|
It returns the name of the slave pseudoterminal device as a
|
|
null-terminated string in the buffer pointed to by
|
|
.IR buf .
|
|
The
|
|
.I buflen
|
|
argument specifies the number of bytes available in
|
|
.IR buf .
|
|
.SH RETURN VALUE
|
|
On success,
|
|
.BR 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.
|
|
.PP
|
|
On success,
|
|
.BR ptsname_r ()
|
|
returns 0.
|
|
On failure, an error number is returned to indicate the error.
|
|
.\" In glibc, the error number is not only returned as the return value
|
|
.\" but also stored in errno. But this is not true for musl libc.
|
|
.SH ERRORS
|
|
.TP
|
|
.B EINVAL
|
|
.RB ( ptsname_r ()
|
|
only)
|
|
.I buf
|
|
is NULL.
|
|
(This error is returned only for
|
|
.\" glibc commit 8f0a947cf55f3b0c4ebdf06953c57eff67a22fa9
|
|
glibc 2.25 and earlier.)
|
|
.TP
|
|
.B ENOTTY
|
|
.I fd
|
|
does not refer to a pseudoterminal master device.
|
|
.TP
|
|
.B ERANGE
|
|
.RB ( ptsname_r ()
|
|
only)
|
|
.I buf
|
|
is too small.
|
|
.SH VERSIONS
|
|
.BR ptsname ()
|
|
is provided in glibc since version 2.1.
|
|
.SH ATTRIBUTES
|
|
For an explanation of the terms used in this section, see
|
|
.BR attributes (7).
|
|
.TS
|
|
allbox;
|
|
lb lb lb
|
|
l l l.
|
|
Interface Attribute Value
|
|
T{
|
|
.BR ptsname ()
|
|
T} Thread safety MT-Unsafe race:ptsname
|
|
T{
|
|
.BR ptsname_r ()
|
|
T} Thread safety MT-Safe
|
|
.TE
|
|
.SH CONFORMING TO
|
|
.BR ptsname ():
|
|
POSIX.1-2001, POSIX.1-2008.
|
|
.PP
|
|
.BR ptsname ()
|
|
is part of the UNIX 98 pseudoterminal support (see
|
|
.BR pts (4)).
|
|
.PP
|
|
.BR ptsname_r ()
|
|
is a Linux extension, that is proposed for inclusion
|
|
.\" FIXME . for later review when Issue 8 is one day released
|
|
.\" http://austingroupbugs.net/tag_view_page.php?tag_id=8
|
|
.\" http://austingroupbugs.net/view.php?id=508
|
|
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
|
|
.I errno
|
|
set to indicate the error.
|
|
Avoid using this function in portable programs.
|
|
.SH SEE ALSO
|
|
.BR grantpt (3),
|
|
.BR posix_openpt (3),
|
|
.BR ttyname (3),
|
|
.BR unlockpt (3),
|
|
.BR pts (4),
|
|
.BR pty (7)
|