1 /***********************************************************************
2 * *
3 * This software is part of the ast package *
4 * Copyright (c) 1992-2012 AT&T Intellectual Property *
5 * and is licensed under the *
6 * Eclipse Public License, Version 1.0 *
7 * by AT&T Intellectual Property *
8 * *
9 * A copy of the License is available at *
10 * http://www.eclipse.org/org/documents/epl-v10.html *
11 * (with md5 checksum b35adb5213ca9657e911e9befb180842) *
12 * *
13 * Information and Software Systems Research *
14 * AT&T Research *
15 * Florham Park NJ *
16 * *
17 * Glenn Fowler <gsf@research.att.com> *
18 * David Korn <dgk@research.att.com> *
19 * *
20 ***********************************************************************/
21 #pragma prototyped
22 /*
23 * David Korn
24 * AT&T Bell Laboratories
25 *
26 * tty
27 */
28
29 static const char usage[] =
30 "[-?\n@(#)$Id: tty (AT&T Research) 2008-03-13 $\n]"
31 USAGE_LICENSE
32 "[+NAME?tty - write the name of the terminal to standard output]"
33 "[+DESCRIPTION?\btty\b writes the name of the terminal that is connected "
34 "to standard input onto standard output. If the standard input is not "
35 "a terminal, \"\bnot a tty\b\" will be written to standard output.]"
36 "[l:line-number?Write the synchronous line number of the terminal on a "
37 "separate line following the terminal name line. If the standard "
38 "input is not a synchronous terminal then "
39 "\"\bnot on an active synchronous line\b\" is written.]"
40 "[s:silent|quiet?Disable the terminal name line. Use \b[[ -t 0 ]]]]\b instead.]"
41 "[+EXIT STATUS?]{"
42 "[+0?Standard input is a tty.]"
43 "[+1?Standard input is not a tty.]"
44 "[+2?Invalid arguments.]"
45 "[+3?A an error occurred.]"
46 "}"
47 ;
48
49
50 #include <cmd.h>
51
52 #if _mac_STWLINE
53 #include <sys/stermio.h>
54 #endif
55
56 int
b_tty(int argc,char ** argv,Shbltin_t * context)57 b_tty(int argc, char** argv, Shbltin_t* context)
58 {
59 register int sflag = 0;
60 register int lflag = 0;
61 register char* tty;
62 #if _mac_STWLINE
63 int n;
64 #endif
65
66 cmdinit(argc, argv, context, ERROR_CATALOG, 0);
67 for (;;)
68 {
69 switch (optget(argv, usage))
70 {
71 case 'l':
72 lflag++;
73 continue;
74 case 's':
75 sflag++;
76 continue;
77 case ':':
78 error(2, "%s", opt_info.arg);
79 break;
80 case '?':
81 error(ERROR_usage(2), "%s", opt_info.arg);
82 break;
83 }
84 break;
85 }
86 if(error_info.errors)
87 error(ERROR_usage(2), "%s", optusage(NiL));
88 if(!(tty=ttyname(0)))
89 {
90 tty = ERROR_translate(0, 0, 0, "not a tty");
91 error_info.errors++;
92 }
93 if(!sflag)
94 sfputr(sfstdout,tty,'\n');
95 if(lflag)
96 {
97 #if _mac_STWLINE
98 if ((n = ioctl(0, STWLINE, 0)) >= 0)
99 error(ERROR_OUTPUT, 1, "synchronous line %d", n);
100 else
101 #endif
102 error(ERROR_OUTPUT, 1, "not on an active synchronous line");
103 }
104 return(error_info.errors);
105 }
106