ctermid(3S)                                           ctermid(3S)



     NAME
          ctermid - generate filename for terminal

     SYNOPSIS
          #include <stdio.h>

          char *ctermid(s)
          char *s;

     DESCRIPTION
          ctermid generates the pathname of the controlling terminal
          for the current process, and stores it in a string.

          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 ctermid, and the address of which is returned.
          Otherwise, s is assumed to point to a character array of at
          least l_ctermid elements; the pathname is placed in this ar-
          ray and the value of s is returned.  The constant l_ctermid
          is defined in the <stdio.h> header file.

     NOTES
          The difference between ctermid and ttyname(3C) is that
          ttyname must be handed a file descriptor and returns the ac-
          tual name of the terminal associated with that file descrip-
          tor, while ctermid returns a string (/dev/tty) that refers
          to the terminal if used as a filename.  For this reason,
          ttyname is useful only if the process already has at least
          one file open to a terminal.

     SEE ALSO
          ttyname(3C).























     April, 1990                                                     1