hpux man page for ctermid

ctermid(3S)															       ctermid(3S)

NAME
       ctermid() - generate file name for terminal

SYNOPSIS
DESCRIPTION
       generates a string that, when used as a pathname, refers to the controlling terminal for the current process.

       If  s is a NULL pointer, the string is stored in an internal static area, the contents of which are overwritten at the next call to and the
       address of which is returned.  Otherwise, s is assumed to point to a character array of at least elements; the path name is placed in  this
       array and the value of s is returned.  The constant is defined in the header file.

       If  the	process  has  no controlling terminal, the pathname for the controlling terminal cannot be determined, or some other error occurs,
       returns an empty string.

       For multi-thread applications, if s is a NULL pointer, the operation is not performed and a NULL pointer is returned.

   Notes
       The difference between and is that must be handed a file descriptor and returns the actual name of the terminal associated with	that  file
       descriptor,  while  returns  a  string  that refers to the terminal if used as a file name.  (see ttyname(3C)).	Thus is useful only if the
       process already has at least one file open to a terminal.

SEE ALSO
       ttyname(3C), thread_safety(5).

STANDARDS CONFORMANCE
																       ctermid(3S)