xref: /aosp_15_r20/external/toybox/toys/posix/tty.c (revision cf5a6c84e2b8763fc1a7db14496fd4742913b199)
1*cf5a6c84SAndroid Build Coastguard Worker /* tty.c - Show stdin's terminal name
2*cf5a6c84SAndroid Build Coastguard Worker  *
3*cf5a6c84SAndroid Build Coastguard Worker  * Copyright 2011 Rob Landley <[email protected]>
4*cf5a6c84SAndroid Build Coastguard Worker  *
5*cf5a6c84SAndroid Build Coastguard Worker  * See http://opengroup.org/onlinepubs/9699919799/utilities/tty.html
6*cf5a6c84SAndroid Build Coastguard Worker 
7*cf5a6c84SAndroid Build Coastguard Worker USE_TTY(NEWTOY(tty, "s", TOYFLAG_USR|TOYFLAG_BIN))
8*cf5a6c84SAndroid Build Coastguard Worker 
9*cf5a6c84SAndroid Build Coastguard Worker config TTY
10*cf5a6c84SAndroid Build Coastguard Worker   bool "tty"
11*cf5a6c84SAndroid Build Coastguard Worker   default y
12*cf5a6c84SAndroid Build Coastguard Worker   help
13*cf5a6c84SAndroid Build Coastguard Worker     usage: tty [-s]
14*cf5a6c84SAndroid Build Coastguard Worker 
15*cf5a6c84SAndroid Build Coastguard Worker     Show filename of terminal connected to stdin. If none print "not a tty"
16*cf5a6c84SAndroid Build Coastguard Worker     and exit with nonzero status.
17*cf5a6c84SAndroid Build Coastguard Worker 
18*cf5a6c84SAndroid Build Coastguard Worker     -s	Silent, exit code only
19*cf5a6c84SAndroid Build Coastguard Worker */
20*cf5a6c84SAndroid Build Coastguard Worker 
21*cf5a6c84SAndroid Build Coastguard Worker #include "toys.h"
22*cf5a6c84SAndroid Build Coastguard Worker 
tty_main(void)23*cf5a6c84SAndroid Build Coastguard Worker void tty_main(void)
24*cf5a6c84SAndroid Build Coastguard Worker {
25*cf5a6c84SAndroid Build Coastguard Worker   char *tty = ttyname(0);
26*cf5a6c84SAndroid Build Coastguard Worker 
27*cf5a6c84SAndroid Build Coastguard Worker   toys.exitval = !tty;
28*cf5a6c84SAndroid Build Coastguard Worker   if (!toys.optflags) puts(tty ? : "not a tty");
29*cf5a6c84SAndroid Build Coastguard Worker }
30