43 lines
1.1 KiB
C
43 lines
1.1 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* tty implementation for busybox
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*
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* Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
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*
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* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
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*/
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/* BB_AUDIT SUSv3 compliant */
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/* http://www.opengroup.org/onlinepubs/007904975/utilities/tty.html */
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#include "libbb.h"
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int tty_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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int tty_main(int argc, char **argv)
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{
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const char *s;
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USE_INCLUDE_SUSv2(int silent;) /* Note: No longer relevant in SUSv3. */
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int retval;
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xfunc_error_retval = 2; /* SUSv3 requires > 1 for error. */
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USE_INCLUDE_SUSv2(silent = getopt32(argv, "s");)
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/* gnu tty outputs a warning that it is ignoring all args. */
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bb_warn_ignoring_args(argc - optind);
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retval = 0;
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s = ttyname(0);
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if (s == NULL) {
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/* According to SUSv3, ttyname can on fail with EBADF or ENOTTY.
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* We know the file descriptor is good, so failure means not a tty. */
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s = "not a tty";
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retval = 1;
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}
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USE_INCLUDE_SUSv2(if (!silent) puts(s);)
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SKIP_INCLUDE_SUSv2(puts(s);)
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fflush_stdout_and_exit(retval);
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}
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