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[thirdparty/man-pages.git] / man3 / getttyent.3

.\"  Copyright 2002 walter harms (walter.harms@informatik.uni-oldenburg.de)
.\"
.\" %%%LICENSE_START(GPL_NOVERSION_ONELINE)
.\" Distributed under GPL
.\" %%%LICENSE_END
.\"
.TH GETTTYENT 3 2017-09-15  "GNU" "Linux Programmer's Manual"
.SH NAME
getttyent, getttynam, setttyent, endttyent \- get ttys file entry
.SH SYNOPSIS
.B "#include <ttyent.h>"
.PP
.B "struct ttyent *getttyent(void);"
.PP
.BI "struct ttyent *getttynam(const char *" name );
.PP
.B "int setttyent(void);"
.PP
.B "int endttyent(void);"
.SH DESCRIPTION
These functions provide an interface to the file
.B _PATH_TTYS
(e.g.,
.IR /etc/ttys ).
.PP
The function
.BR setttyent ()
opens the file or rewinds it if already open.
.PP
The function
.BR endttyent ()
closes the file.
.PP
The function
.BR getttynam ()
searches for a given terminal name in the file.
It returns a pointer to a
.I ttyent
structure (description below).
.PP
The function
.BR getttyent ()
opens the file
.B _PATH_TTYS
(if necessary) and returns the first entry.
If the file is already open, the next entry.
The
.I ttyent
structure has the form:
.PP
.in +4n
.EX
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 */
};
.EE
.in
.PP
.I ty_status
can be:
.PP
.in +4n
.EX
#define TTY_ON     0x01  /* enable logins (start ty_getty program) */
#define TTY_SECURE 0x02  /* allow UID 0 to login */
.EE
.in
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lbw25 lb lb
l l l.
Interface	Attribute	Value
T{
.BR getttyent (),
.BR setttyent (),
.BR endttyent (),
.BR getttynam ()
T}	Thread safety	MT-Unsafe race:ttyent
.TE
.SH CONFORMING TO
Not in POSIX.1.
Present on the BSDs, and perhaps other systems.
.SH NOTES
Under Linux, the file
.IR /etc/ttys ,
and the functions described above, are not used.
.SH SEE ALSO
.BR ttyname (3),
.BR ttyslot (3)