ttyname_r(3C)

NAME

     ttyname, ttyname_r - find pathname of a terminal

SYNOPSIS

     #include <unistd.h>

     char *ttyname(int fildes);

     char *ttyname_r(int fildes, char *name, int namelen);

  POSIX
     cc [ flag ...] file ... -D_POSIX_PTHREAD_SEMANTICS [ library ... ]

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

DESCRIPTION

     The ttyname() function returns a pointer to  a  string  con-
     taining the null-terminated path name of the terminal device
     associated with file descriptor fildes.   The  return  value
     may  point  to  static  data whose content is overwritten by
     each call.

     The ttyname_r()  function  has  the  same  functionality  as
     ttyname()  except  that the caller must supply a buffer name
     with length namelen to store the result; this buffer must be
     at  least _POSIX_PATH_MAX   in size (defined in <limits.h>).
     The POSIX version (see standards(5)) of ttyname_r() takes  a
     namesize parameter of type size_t.

RETURN VALUES

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

     The POSIX ttyname_r() returns zero  if  successful,  or  the
     error number upon failure.

ERRORS

     The ttyname_r() function will fail if:

     ERANGE
           The size of the buffer is smaller than the  result  to
           be returned.

     The ttyname() function may fail if:

     EBADF The fildes argument is not a valid file descriptor.

     ENOTTY
           The fildes argument does not refer to a terminal  dev-
           ice.

FILES

     /dev/*
           device file

ATTRIBUTES

     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | MT-Level                    | See NOTES below.            |
    |_____________________________|_____________________________|

SEE ALSO

     Intro(3), gettext(3C), setlocale(3C),  attributes(5),  stan-
     dards(5)

NOTES

     When compiling multithreaded programs, see  Intro(3),  Notes
     On Multithreaded Applications.

     If the application is  linked  with  -lintl,  then  messages
     printed from this function are in the native language speci-
     fied by the LC_MESSAGES locale category; see setlocale(3C).

     The return value points to  static  data  whose  content  is
     overwritten by each call.

     The ttyname() is Unsafe in multithreaded applications.   The
     ttyname_r() function is MT-Safe, and should be used instead.

     Solaris 2.4 and earlier releases provided definitions of the
     ttyname_r()  interface as specified in POSIX.1c Draft 6. The
     final POSIX.1c standard changed the interface  as  described
     above.  Support  for  the  Draft 6 interface is provided for
     compatibility only  and  may  not  be  supported  in  future
     releases.  New  applications  and  libraries  should use the
     POSIX standard interface.