centos man page for getttyent

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

NAME
       getttyent, getttynam, setttyent, endttyent - get ttys file entry

SYNOPSIS
       #include <ttyent.h>

       struct ttyent *getttyent(void);

       struct ttyent *getttynam(const char *name);

       int setttyent(void);

       int endttyent(void);

DESCRIPTION
       These functions provide an interface to the file _PATH_TTYS (e.g., /etc/ttys).

       The function setttyent() opens the file or rewinds it if already open.

       The function endttyent() closes the file.

       The function getttynam() searches for a given terminal name in the file.  It returns a pointer to a ttyent structure (description below).

       The  function  getttyent()  opens  the  file  _PATH_TTYS (if necessary) and returns the first entry.  If the file is already open, the next
       entry.  The ttyent structure has the form:

	   struct ttyent {
	       char *ty_name;	  /* terminal device name */
	       char *ty_getty;	  /* command to execute, usually getty */
	       char *ty_type;	  /* terminal type for termcap */
	       int   ty_status;   /* status flags */
	       char *ty_window;   /* command to start up window manager */
	       char *ty_comment;  /* comment field */
	   };

       ty_status can be:

       #define TTY_ON	  0x01	/* enable logins (start ty_getty program) */
       #define TTY_SECURE 0x02	/* allow UID 0 to login */

ATTRIBUTES
   Multithreading (see pthreads(7))
       The getttyent() function returns a pointer to a static variable, so it is not thread-safe.

       The setttyent() and endttyent() functions use a static variable, so they are not thread-safe.

       The getttynam() function calls thread-unsafe function getttyent() so it is not thread-safe.

CONFORMING TO
       Not in POSIX.1-2001.  Present on the BSDs, and perhaps other systems.

NOTES
       Under Linux the file /etc/ttys, and the functions described above, are not used.

SEE ALSO
       ttyname(3), ttyslot(3)

COLOPHON
       This page is part of release 3.53 of the Linux man-pages project.  A description of the project, and information about reporting bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

GNU
								    2013-07-22							      GETTTYENT(3)