getttyent(3)getttyent(3)NAME
getttyent, getttyent_r, getttynam, getttynam_r, setttyent, setttyent_r,
endttyent, endttyent_r - Get a /etc/securettys file entry
SYNOPSIS
#include <ttyent.h>
struct ttyent *getttyent(
void ); struct ttyent *getttynam(
const char *name ); int setttyent(
void ); void endttyent(
void );
The following obsolete functions are supported in order to maintain
backward compatibility with previous versions of the operating system.
You should not use them in new designs. int getttyent_r(
struct ttyent *tte,
char *buf,
int len,
FILE **tty_fp ); int getttynam_r(
const char *name,
struct ttyent *tte,
char *buf,
int len ); int setttyent_r(
FILE **tty_fp ); void endttyent_r(
FILE **tty_fp );
LIBRARY
Standard C Library (libc)
PARAMETERS
Points to the ttyent structure. The ttyent.h header file defines the
ttyent structure. Specifies the name of the requested tty description.
Is data for the tty. Specifies the length of buf. Specifies a secure
ttys file stream.
DESCRIPTION
The getttyent() and getttynam() functions each return a pointer to an
object that has the following ttyent fields. These fields describe a
line from the secure tty description file.
The members of the structure include the following: Name of the charac‐
ter-special file. The string "none". The string "none". A mask of
bit fields. The TTY_SECURE option indicates users with a user ID of 0
(zero) are allowed to log in on this terminal. A NULL pointer A NULL
pointer.
If any of the fields pointing to character strings are unspecified,
they are returned as NULL pointers. The field ty_status will be 0
(zero) if root logins are not allowed.
The getttyent() function reads the next line from the tty file, opening
the file if necessary. The setttyent() function rewinds the file if
open, or opens the file if it is unopened. The endttyent() function
closes any open files.
The getttynam() function searches from the beginning of the file until
a matching name is found or until EOF (End-Of-File) is encountered.
NOTES
The getttyent(), setttyent(), endttyent(), and getttynam() functions
return a pointer to thread-specific data. Subsequent calls to these
functions from the same thread overwrite this data.
The getttyent_r(), setttyent_r(), endttyent_r(), and getttynam_r()
functions are obsolete reentrant versions of these functions. They are
supported in order to maintain backward compatibility with previous
versions of the operating system and should not be used in new designs.
Note that you must initialize the *tty_fp parameter to NULL before its
first access by any of these functions.
RETURN VALUES
Upon successful completion, the getttyent() and getttynam() functions
return a pointer to a ttyent structure. If they fail or reach the end
of the terminal control database file, they return a null pointer.
Upon successful completion, the setttyent() function returns a value of
1. Upon failure, it returns a value of 0 (zero).
Upon successful completion, the getttyent_r() and getttynam_r() func‐
tions store the ttyent structure in the location pointed to by tte, and
return a value of 0 (zero). Upon failure, they return a value of -1.
Upon successful completion, the setttyent_r() function returns a value
of 0 (zero). Upon failure, it returns a value of -1.
ERRORS
If any of the following conditions occurs, the getttyent_r() or gettty‐
nam_r() functions set errno to the corresponding value: The search
failed.
In addition, if any of the following conditions occurs, the gett‐
tyent_r() or setttyent_r() functions set errno to the corresponding
value: The tty_fp, tte, or buf parameter is invalid, or the len parame‐
ter is too small.
FILES
/etc/securettys Contains the terminal control database file.
SEE ALSO
Commands: login(1)
Files: securettys(4).
getttyent(3)