@node ptsname_r
@subsection @code{ptsname_r}
@findex ptsname_r

Documentation:
@itemize
@item
@ifinfo
@ref{Allocation,,Allocating Pseudo-Terminals,libc},
@end ifinfo
@ifnotinfo
@url{https://www.gnu.org/software/libc/manual/html_node/Allocation.html},
@end ifnotinfo
@item
@uref{https://www.kernel.org/doc/man-pages/online/pages/man3/ptsname_r.3.html,,man ptsname_r}.
@end itemize

Gnulib module: ptsname_r

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
Mac OS X 10.12, FreeBSD 12.0, NetBSD 5.0, OpenBSD 6.7, Minix 3.1.8,
AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 11.4, Cygwin 1.7.9, mingw,
MSVC 14.
@item
When this function fails, it returns -1 instead of the error code
on some platforms:
macOS 11.1, FreeBSD 13.0, Android 4.3.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
When this function fails, it returns 0 and stores an empty string as result
on some platforms:
Cygwin 2.9.
@end itemize

Note: Portable programs should expect to find the error code as the
return value of this function, not as the value of @code{errno}.
This is needed for compatibility with musl libc and with the
forthcoming POSIX Issue 8.