PTSNAME(3)		   Linux Programmer's Manual		    PTSNAME(3)



NAME
       ptsname, ptsname_r - get the name of the slave pseudoterminal

SYNOPSIS
       #define _XOPEN_SOURCE	   /* See feature_test_macros(7) */
       #include <stdlib.h>

       char *ptsname(int fd);

       #define _GNU_SOURCE	   /* See feature_test_macros(7) */
       #include <stdlib.h>

       int ptsname_r(int fd, char *buf, size_t buflen);

DESCRIPTION
       The  ptsname()  function	 returns  the name of the slave pseudoterminal
       device 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, a nonzero value is
       returned and errno is set to indicate the error.

ERRORS
       EINVAL (ptsname_r() only) buf is NULL.

       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
       attributes(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 4.10 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/.



				  2016-12-12			    PTSNAME(3)