PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

TTYNAME(3P)               POSIX Programmer's Manual              TTYNAME(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       ttyname, ttyname_r — find the pathname of a terminal

SYNOPSIS         top

       #include <unistd.h>

       char *ttyname(int fildes);
       int ttyname_r(int fildes, char *name, size_t namesize);

DESCRIPTION         top

       The ttyname() function shall return a pointer to a string containing
       a null-terminated pathname of the terminal associated with file
       descriptor fildes.  The application shall not modify the string
       returned. The returned pointer might be invalidated or the string
       content might be overwritten by a subsequent call to ttyname().

       The ttyname() function need not be thread-safe.

       The ttyname_r() function shall store the null-terminated pathname of
       the terminal associated with the file descriptor fildes in the
       character array referenced by name.  The array is namesize characters
       long and should have space for the name and the terminating null
       character. The maximum length of the terminal name shall be
       {TTY_NAME_MAX}.

RETURN VALUE         top

       Upon successful completion, ttyname() shall return a pointer to a
       string. Otherwise, a null pointer shall be returned and errno set to
       indicate the error.

       If successful, the ttyname_r() function shall return zero. Otherwise,
       an error number shall be returned to indicate the error.

ERRORS         top

       The ttyname() function may fail if:

       EBADF  The fildes argument is not a valid file descriptor.

       ENOTTY The file associated with the fildes argument is not a
              terminal.

       The ttyname_r() function may fail if:

       EBADF  The fildes argument is not a valid file descriptor.

       ENOTTY The file associated with the fildes argument is not a
              terminal.

       ERANGE The value of namesize is smaller than the length of the string
              to be returned including the terminating null character.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       None.

RATIONALE         top

       The term ``terminal'' is used instead of the historical term
       ``terminal device'' in order to avoid a reference to an undefined
       term.

       The thread-safe version places the terminal name in a user-supplied
       buffer and returns a non-zero value if it fails. The non-thread-safe
       version may return the name in a static data area that may be
       overwritten by each call.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       The Base Definitions volume of POSIX.1‐2008, unistd.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) In the event of any discrepancy between this version and
       the original IEEE and The Open Group Standard, the original IEEE and
       The Open Group Standard is the referee document. The original
       Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                         TTYNAME(3P)